fix(coderd): remove deprecated AITaskSidebarApp column (#20680)

This column was no longer used in `v2.28` and the codersdk field
deprecated. Both can now be dropped in `v2.29`.

Closes coder/internal#974

coderd/database/dbgen/dbgen.go

@@ -451,7 +451,6 @@ func WorkspaceBuild(t testing.TB, db database.Store, orig database.WorkspaceBuil
 	buildID := takeFirst(orig.ID, uuid.New())
 	jobID := takeFirst(orig.JobID, uuid.New())
 	hasAITask := takeFirst(orig.HasAITask, sql.NullBool{})
-	sidebarAppID := takeFirst(orig.AITaskSidebarAppID, uuid.NullUUID{})
 	hasExternalAgent := takeFirst(orig.HasExternalAgent, sql.NullBool{})
 	var build database.WorkspaceBuild
 	err := db.InTx(func(db database.Store) error {
@@ -491,7 +490,6 @@ func WorkspaceBuild(t testing.TB, db database.Store, orig database.WorkspaceBuil
 				ID:               buildID,
 				HasAITask:        hasAITask,
 				HasExternalAgent: hasExternalAgent,
-				SidebarAppID:     sidebarAppID,
 				UpdatedAt:        dbtime.Now(),
 			}))
 		}