Add new compute capabilities as advisory

Based on our analysis [1], there were several compute tests
available which weren't included in any interop guideline.
This commit adds those tests under a few new capabilities which
are added as advisory for now. They can be moved to required
after one cycle being under advisory. Interop WG will review
these tests for inclusion for the next guideline cycle.

[1] https://etherpad.opendev.org/p/refstack-test-analysis

Change-Id: Iff7b96c9567811af85c44853fad99706eed5f11e

guidelines/next.json

@@ -167,7 +167,12 @@
           "identity-v3-application-credentials",
           "identity-v3-users",
           "identity-v3-domains",
-          "volumes-v3-snapshots-list"
+          "volumes-v3-snapshots-list",
+          "compute-images-metadata-delete",
+          "compute-images-metadata-get",
+          "compute-images-metadata-list",
+          "compute-images-metadata-set",
+          "compute-images-metadata-update"
         ],
         "deprecated": [],
         "removed": []
@@ -313,6 +318,137 @@
         }
       }
     },
+    "compute-images-metadata-delete": {
+      "achievements": [
+        "complete",
+        "doc",
+        "proximity",
+        "clients",
+        "discover",
+        "sticky",
+        "atomic",
+        "stable",
+        "tools"
+      ],
+      "admin": false,
+      "description": "Image metadata deletion within the Compute API",
+      "project": "nova",
+      "required_since": "2021.07",
+      "tests": {
+        "tempest.api.compute.images.test_image_metadata.ImagesMetadataTestJSON.test_delete_image_metadata_item": {
+          "idempotent_id": "id-a013796c-ba37-4bb5-8602-d944511def14"
+        },
+        "tempest.api.compute.images.test_image_metadata_negative.ImagesMetadataNegativeTestJSON.test_delete_nonexistent_image_metadata_item": {
+          "idempotent_id": "id-848e157f-6bcf-4b2e-a5dd-5124025a8518"
+        }
+      }
+    },
+    "compute-images-metadata-get": {
+      "achievements": [
+        "complete",
+        "doc",
+        "proximity",
+        "clients",
+        "discover",
+        "sticky",
+        "atomic",
+        "stable",
+        "tools"
+      ],
+      "admin": false,
+      "description": "Get image metadata using the Compute API",
+      "project": "nova",
+      "required_since": "2021.07",
+      "tests": {
+        "tempest.api.compute.images.test_image_metadata.ImagesMetadataTestJSON.test_get_image_metadata_item": {
+          "idempotent_id": "id-4f5db52f-6685-4c75-b848-f4bb363f9aa6"
+        },
+        "tempest.api.compute.images.test_image_metadata_negative.ImagesMetadataNegativeTestJSON.test_get_nonexistent_image_metadata_item": {
+          "idempotent_id": "id-41ae052c-6ee6-405c-985e-5712393a620d"
+        }
+      }
+    },
+    "compute-images-metadata-list": {
+      "achievements": [
+        "complete",
+        "doc",
+        "proximity",
+        "clients",
+        "discover",
+        "sticky",
+        "atomic",
+        "stable",
+        "tools"
+      ],
+      "admin": false,
+      "description": "List image metadata using the Compute API",
+      "project": "nova",
+      "required_since": "2021.07",
+      "tests": {
+        "tempest.api.compute.images.test_image_metadata.ImagesMetadataTestJSON.test_list_image_metadata": {
+          "idempotent_id": "id-37ec6edd-cf30-4c53-bd45-ae74db6b0531"
+        },
+        "tempest.api.compute.images.test_image_metadata_negative.ImagesMetadataNegativeTestJSON.test_list_nonexistent_image_metadata": {
+          "idempotent_id": "id-94069db2-792f-4fa8-8bd3-2271a6e0c095"
+        }
+      }
+    },
+    "compute-images-metadata-set": {
+      "achievements": [
+        "complete",
+        "doc",
+        "proximity",
+        "clients",
+        "discover",
+        "sticky",
+        "atomic",
+        "stable",
+        "tools"
+      ],
+      "admin": false,
+      "description": "Set image metadata using the Compute API",
+      "project": "nova",
+      "required_since": "2021.07",
+      "tests": {
+        "tempest.api.compute.images.test_image_metadata.ImagesMetadataTestJSON.test_set_image_metadata": {
+          "idempotent_id": "id-ece7befc-d3ce-42a4-b4be-c3067a418c29"
+        },
+        "tempest.api.compute.images.test_image_metadata.ImagesMetadataTestJSON.test_set_image_metadata_item": {
+          "idempotent_id": "id-f2de776a-4778-4d90-a5da-aae63aee64ae"
+        },
+        "tempest.api.compute.images.test_image_metadata_negative.ImagesMetadataNegativeTestJSON.test_set_nonexistent_image_metadata": {
+          "idempotent_id": "id-dc64f2ce-77e8-45b0-88c8-e15041d08eaf"
+        },
+        "tempest.api.compute.images.test_image_metadata_negative.ImagesMetadataNegativeTestJSON.test_set_nonexistent_image_metadata_item": {
+          "idempotent_id": "id-2154fd03-ab54-457c-8874-e6e3eb56e9cf"
+        }
+      }
+    },
+    "compute-images-metadata-update": {
+      "achievements": [
+        "complete",
+        "doc",
+        "proximity",
+        "clients",
+        "discover",
+        "sticky",
+        "atomic",
+        "stable",
+        "tools"
+      ],
+      "admin": false,
+      "description": "Upadate image metadata using the Compute API",
+      "project": "nova",
+      "required_since": "2021.07",
+      "tests": {
+        "tempest.api.compute.images.test_image_metadata.ImagesMetadataTestJSON.test_update_image_metadata": {
+          "idempotent_id": "id-7b491c11-a9d5-40fe-a696-7f7e03d3fea2"
+        },
+        "tempest.api.compute.images.test_image_metadata_negative.ImagesMetadataNegativeTestJSON.test_update_nonexistent_image_metadata": {
+          "idempotent_id": "id-a403ef9e-9f95-427c-b70a-3ce3388796f1"
+        }
+      }
+    },
     "compute-instance-actions-get": {
       "achievements": [
         "foundation",