Specify gerrit triggers

Needed once https://review.openstack.org/#/c/39186/ is merged.

Change-Id: Idba2f0a8ec30f838c6ed3acb41c0e617df5afb8d

modules/openstack_project/files/zuul/layout-dev.yaml

@@ -6,6 +6,7 @@ pipelines:
     description: This pipeline is used for silently testing new jobs.
     manager: IndependentPipelineManager
     trigger:
+      gerrit:
         - event: patchset-created
         - event: comment-added
           comment_filter: (?i)^\s*recheck(( (?:bug|lp)[\s#:]*(\d+))|( no bug))\s*$

modules/openstack_project/files/zuul/layout.yaml

@@ -8,6 +8,7 @@ pipelines:
     manager: IndependentPipelineManager
     precedence: low
     trigger:
+      gerrit:
         - event: patchset-created
         - event: comment-added
           comment_filter: (?i)^\s*recheck(( (?:bug|lp)[\s#:]*(\d+))|( no bug))\s*$
@@ -22,6 +23,7 @@ pipelines:
     manager: DependentPipelineManager
     precedence: high
     trigger:
+      gerrit:
         - event: comment-added
           approval:
             - approved: 1
@@ -39,6 +41,7 @@ pipelines:
     description: This pipeline runs jobs that operate after each change is merged.
     manager: IndependentPipelineManager
     trigger:
+      gerrit:
         - event: ref-updated
           ref: ^(?!(devnull|refs/.*)).*$
 
@@ -47,6 +50,7 @@ pipelines:
     manager: IndependentPipelineManager
     precedence: high
     trigger:
+      gerrit:
         - event: ref-updated
           ref: ^refs/tags/([0-9]+\.)+[0-9]*(alpha|beta|candidate|rc|a|b|c|r|g)[0-9]*$
 
@@ -55,6 +59,7 @@ pipelines:
     manager: IndependentPipelineManager
     precedence: high
     trigger:
+      gerrit:
         - event: ref-updated
           ref: ^refs/tags/([0-9]+\.)+[0-9]+$
 
@@ -63,6 +68,7 @@ pipelines:
     manager: IndependentPipelineManager
     precedence: low
     trigger:
+      gerrit:
         - event: patchset-created
         - event: comment-added
           comment_filter: (?i)^\s*recheck(( (?:bug|lp)[\s#:]*(\d+))|( no bug))\s*$