Try to fix flaky paste tests (#182574)

These tests fail occasionally in CI, seemingly only on linux. This tries to fix this by:

- Adding retries
- Switching back to use `teardown` to disposed of things. `usingDisposable` may not clean up properly if the test times out

extensions/vscode-api-tests/src/utils.ts

@@ -62,17 +62,6 @@ export function disposeAll(disposables: vscode.Disposable[]) {
 	vscode.Disposable.from(...disposables).dispose();
 }
 
-export function usingDisposables<R>(fn: (this: Mocha.Context, store: vscode.Disposable[]) => Promise<R>) {
-	return async function (this: Mocha.Context): Promise<R> {
-		const disposables: vscode.Disposable[] = [];
-		try {
-			return await fn.call(this, disposables);
-		} finally {
-			disposeAll(disposables);
-		}
-	};
-}
-
 export function delay(ms: number) {
 	return new Promise(resolve => setTimeout(resolve, ms));
 }