Add launch configuration to run single unit test (#1796)

.vscode/launch.json

@@ -45,6 +45,30 @@
       "console": "integratedTerminal",
       "internalConsoleOptions": "neverOpen"
     },
+    {
+      "name": "Launch Selected Unit Test (vscode-codeql)",
+      "type": "node",
+      "request": "launch",
+      "program": "${workspaceFolder}/extensions/ql-vscode/node_modules/jest/bin/jest.js",
+      "showAsyncStacks": true,
+      "cwd": "${workspaceFolder}/extensions/ql-vscode",
+      "env": {
+        "LANG": "en-US",
+        "TZ": "UTC"
+      },
+      "args": [
+        "--projects",
+        "test",
+        "-i",
+        "${relativeFile}",
+        "-t",
+        "${selectedText}"
+      ],
+      "stopOnEntry": false,
+      "sourceMaps": true,
+      "console": "integratedTerminal",
+      "internalConsoleOptions": "neverOpen"
+    },
     {
       "name": "Launch Unit Tests - React (vscode-codeql)",
       "type": "node",