Switch to vscodetestcover for running extension tests (#5458)

* Update vscode dependency (needed for test runner) to pull latest 1.x version

* Update to use 1.1.5 instead

* Undo change to vscode engine version

* Switch to using vscodetestcover for running tests

* Switch to cobertura output for coverage reports

* Remove vscode dependency from profiler extension

* Update yarn.lock with combined changes

extensions/notebook/coverageConfig.json

@@ -0,0 +1,18 @@
+{
+	"enabled": false,
+	"relativeSourcePath": "..",
+	"relativeCoverageDir": "../../coverage",
+	"ignorePatterns": [
+		"**/node_modules/**",
+		"**/test/**"
+	],
+	"includePid": false,
+	"reports": [
+		"cobertura"
+	],
+	"verbose": false,
+	"remapOptions": {
+		"basePath": ".",
+		"useAbsolutePaths": true
+	}
+}