Docs standardization

library/database/postgresql_privs

@@ -86,7 +86,7 @@ options:
       - I(grant_option) only has an effect if I(state) is C(present).
       - 'Alias: I(admin_option)'
     required: no
-    choices: [yes, no]
+    choices: ['yes', 'no']
   host:
     description:
       - Database host address. If unspecified, connect via Unix socket.

library/database/postgresql_user

@@ -55,7 +55,7 @@ options:
     description:
       - if C(yes), fail when user can't be removed. Otherwise just log and continue
     required: false
-    default: yes
+    default: 'yes'
     choices: [ "yes", "no" ]
   login_user:
     description: