Integration test update: test_fallback_admin_user (#2884)

## Changes

This updates an integration test to more thoroughly verify that we can
locate the user-name of an administrator.

### Linked issues

Follows: #2774

### Tests

 - updated integration test

Author: asnare

tests/integration/framework/test_owners.py

@@ -1,8 +1,53 @@
+import json
+
+from databricks.sdk import WorkspaceClient
+from databricks.sdk.service import iam
+
 from databricks.labs.ucx.contexts.workflow_task import RuntimeContext
 
 
-def test_fallback_workspace_admin(installation_ctx: RuntimeContext) -> None:
-    """Verify that a workspace administrator can be found for our integration environment."""
+def _find_admins_group_id(ws: WorkspaceClient) -> str:
+    for group in ws.groups.list(attributes="id,displayName,meta", filter='displayName eq "admins"'):
+        if group.id and group.display_name == "admins" and group.meta and group.meta.resource_type == "WorkspaceGroup":
+            return group.id
+    msg = f"Could not locate workspace group in {ws.get_workspace_id()}: admins"
+    raise RuntimeError(msg)
+
+
+def _find_user_with_name(ws: WorkspaceClient, user_name: str) -> iam.User:
+    for user in ws.users.list(attributes="active,groups,roles,userName", filter=f"userName eq {json.dumps(user_name)}"):
+        if user.user_name == user_name:
+            return user
+    # Use debugger if this is not working to avoid internal usernames in public issues or CI logs.
+    msg = f"Could not locate user in workspace {ws.get_workspace_id()}: **REDACTED**"
+    raise RuntimeError(msg)
+
+
+def _user_is_member_of_group(user: iam.User, group_id: str) -> bool:
+    assert user.groups
+    return any(g for g in user.groups if g.value == group_id)
+
+
+def _user_has_role(user: iam.User, role_name: str) -> bool:
+    assert user.roles
+    return any(r for r in user.roles if r.value == role_name)
+
+
+def test_fallback_admin_user(ws, installation_ctx: RuntimeContext) -> None:
+    """Verify that an administrator can be found for our integration environment."""
     an_admin = installation_ctx.administrator_locator.get_workspace_administrator()
 
-    assert "@" in an_admin
+    # The specific admin username that we get here depends on the set of current admins in the integration environment,
+    # so that can't be checked directly. Instead we check that either:
+    #   a) they're a member of the 'admins' workspace; or
+    #   b) are an account admin (with the `account_admin` role assigned).
+    # They must also be an active user.
+    #
+    # References:
+    #   https://learn.microsoft.com/en-us/azure/databricks/admin/users-groups/groups#account-admin
+    #   https://learn.microsoft.com/en-us/azure/databricks/admin/users-groups/groups#account-vs-workspace-group
+    admins_group_id = _find_admins_group_id(ws)
+    the_user = _find_user_with_name(ws, an_admin)
+
+    assert an_admin == the_user.user_name and the_user.active
+    assert _user_is_member_of_group(the_user, admins_group_id) or _user_has_role(the_user, "account_admin")