fix: respect RUN_MYSQL on k8s maple upgrade

During the maple -> nutmeg upgrade on k8s, only wait for mysql when RUN_MYSQL is true.

changelog.d/20230109_100009_codewithemad_upgrade_mysql_issue.md

@@ -0,0 +1 @@
+[Bugfix] Running `tutor k8s upgrade --from=maple` won't apply and won't wait for the MySQL deployment to be ready if `RUN_MYSQL: false` (When you host your MySQL somewhere else like RDS) (by @CodeWithEmad)

tutor/commands/upgrade/k8s.py

@@ -120,13 +120,14 @@ def upgrade_from_maple(context: Context, config: Config) -> None:
     # The environment needs to be updated because the backpopulate/backfill commands are from Nutmeg
     tutor_env.save(context.root, config)
 
-    # Start mysql
-    k8s.kubectl_apply(
-        context.root,
-        "--selector",
-        "app.kubernetes.io/name=mysql",
-    )
-    k8s.wait_for_deployment_ready(config, "mysql")
+    if config["RUN_MYSQL"]:
+        # Start mysql
+        k8s.kubectl_apply(
+            context.root,
+            "--selector",
+            "app.kubernetes.io/name=mysql",
+        )
+        k8s.wait_for_deployment_ready(config, "mysql")
 
     # lms upgrade
     k8s.kubectl_apply(