test/runTest: stop creating ${workspaceFolder} directory

when running tests using `npm run test`, ${workspaceFolder} isn't
resolved. Use the project root directory instead.

Change-Id: I0527d343ddcd2ba3122e6769ae036fb6ba0d3253
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/310075
Trust: Hyang-Ah Hana Kim <hyangah@gmail.com>
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
Reviewed-by: Suzy Mueller <suzmue@golang.org>
TryBot-Result: kokoro <noreply+kokoro@google.com>
diff --git a/test/runTest.ts b/test/runTest.ts
index b44b2f7..de9eaa8 100644
--- a/test/runTest.ts
+++ b/test/runTest.ts
@@ -27,7 +27,7 @@
 			extensionTestsPath,
 			launchArgs: [
 				'--disable-extensions',
-				'--user-data-dir=${workspaceFolder}/.user-data-dir-test',
+				`--user-data-dir=${extensionDevelopmentPath}/.user-data-dir-test`,
 				// https://github.com/microsoft/vscode/issues/115794#issuecomment-774283222
 				'--force-disable-user-env'
 			]
@@ -48,7 +48,7 @@
 			extensionTestsPath: path.resolve(__dirname, './gopls/index'),
 			launchArgs: [
 				'--disable-extensions', // disable all other extensions
-				'--user-data-dir=${workspaceFolder}/.user-data-dir-test',
+				`--user-data-dir=${extensionDevelopmentPath}/.user-data-dir-test`,
 				// https://github.com/microsoft/vscode/issues/115794#issuecomment-774283222
 				'--force-disable-user-env'
 			]