Access control: allow granting a fixed role dynamically based on the startup settings (#43867)

* allow granting a fixed role dynamically depending on startup config

* move role definition for team writing

* undo test changes

* nicer naming

pkg/services/accesscontrol/roles.go

@@ -197,19 +197,6 @@ var (
 			},
 		}),
 	}
-
-	teamsWriterRole = RoleDTO{
-		Name:        teamsWriter,
-		DisplayName: "Teams writer",
-		Description: "Create teams.",
-		Group:       "Teams",
-		Version:     1,
-		Permissions: []Permission{
-			{
-				Action: ActionTeamsCreate,
-			},
-		},
-	}
 )
 
 // Role names definitions
@@ -223,7 +210,6 @@ const (
 	statsReader         = "fixed:stats:reader"
 	usersReader         = "fixed:users:reader"
 	usersWriter         = "fixed:users:writer"
-	teamsWriter         = "fixed:teams:writer"
 )
 
 var (
@@ -243,7 +229,6 @@ var (
 		statsReader:         statsReaderRole,
 		usersReader:         usersReaderRole,
 		usersWriter:         usersWriterRole,
-		teamsWriter:         teamsWriterRole,
 	}
 
 	// FixedRoleGrants specifies which built-in roles are assigned
@@ -262,7 +247,6 @@ var (
 		string(models.ROLE_ADMIN): {
 			orgUsersReader,
 			orgUsersWriter,
-			teamsWriter,
 		},
 		string(models.ROLE_EDITOR): {
 			datasourcesExplorer,