Fix getUriForConnection API returning wrong URIs (#2202)

* Fix connection URI api to return working URI

* run tsfmt

* Keep using hand-built connection string for now in import

* Use connection ID instead of URI to get connection string

src/sqltest/stubs/connectionManagementService.test.ts

@@ -254,7 +254,7 @@ export class TestConnectionManagementService implements IConnectionManagementSer
 		return undefined;
 	}
 
-	getConnectionString(ownerUri: string): Thenable<string> {
+	getConnectionString(connectionId: string): Thenable<string> {
 		return undefined;
 	}