Pick up new TS version for building VS Code

Fixes a few instances of `Promise.all` and also adds an any cast to workaround an issue

extensions/github/src/pushErrorHandler.ts

@@ -103,7 +103,8 @@ async function handlePushError(repository: Repository, remote: Remote, refspec:
 					title = commit.message.replace(/\n.*$/m, '');
 				}
 
-				const res = await octokit.pulls.create({
+				// TODO: mjbvz: TS 4.5 workaround
+				const res = await (octokit as any).pulls.create({
 					owner,
 					repo,
 					title,