Different concurrency for tempest and accounts

It's better to generate more accounts in accounts.yaml file, otherwise
some tests may fail because they are trying to access certain credentials
with certian roles which are being used by other tests at that moment.

Change-Id: I698b1b83864009a299ca51c10f8a36e73793369d

roles/generate-accounts-file/README.rst

@@ -12,8 +12,8 @@ which may be there.
 
 **Role Variables**
 
-.. zuul:rolevar:: tempest_concurrency
-   :default: 2
+.. zuul:rolevar:: tempest_account_concurrency
+   :default: 3
 
    A number of parallel test processes.
 

roles/generate-accounts-file/defaults/main.yaml

@@ -1,7 +1,8 @@
-# Here, we set tempest_concurrency to 3 because with concurrency 2 generate
-# only 10 accounts, and sometimes the tests fail because the account is being
-# used by another test, so it's a good idea to have tempest_concurrency always
-# bigger then tempest test concurrency (in our jobs is set to 2)
-tempest_concurrency: 3
+# Here, we set tempest_account_concurrency to 3 because with concurrency 2
+# generate only 10 accounts, and sometimes the tests fail because the account
+# is being used by another test, so it's a good idea to have
+# tempest_account_concurrency alway bigger then tempest test concurrency
+# (in our jobs is set to 2)
+tempest_account_concurrency: 3
 virtualenvs:
     tempest: ~/.virtualenvs/.tempest

roles/generate-accounts-file/tasks/main.yaml

@@ -46,7 +46,7 @@
         printenv
         tempest account-generator \
             --config-file ./etc/tempest.conf \
-            --concurrency {{ tempest_concurrency }} \
+            --concurrency {{ tempest_account_concurrency }} \
             etc/accounts.yaml
     args:
         executable: /bin/bash