Fix removing tunnels when the tunnel factory throws an error (microsoft#186566)

* Await the tunnel promise

* Add null check

* nit: use undefined

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Co-authored-by: Alex Ross <[email protected]>

Author: joshaber

src/vs/platform/tunnel/common/tunnel.ts

@@ -416,7 +416,7 @@ export abstract class AbstractTunnelService implements ITunnelService {
 		const hostMap = this._tunnels.get(remoteHost);
 		if (hostMap) {
 			const tunnel = hostMap.get(remotePort);
-			const tunnelResult = await tunnel;
+			const tunnelResult = tunnel ? await tunnel.value : undefined;
 			if (!tunnelResult) {
 				hostMap.delete(remotePort);
 			}