testing: add context keys for testing/item/context contribution (microsoft#182529)

For microsoft/vscode-python#21238 (comment)

Author: connor4312

src/vs/workbench/contrib/testing/browser/testingExplorerView.ts

@@ -1394,6 +1394,12 @@ const getActionableElementActions = (
 		], [
 			TestingContextKeys.supportsContinuousRun.key,
 			supportsCr,
+		], [
+			TestingContextKeys.controllerId.key,
+			test.controllerId,
+		], [
+			TestingContextKeys.testItemExtId.key,
+			test.item.extId,
 		]);
 	}