[vscode] Add file watcher excludes to fix CPU fan spin by cpptools. (#…

…20193)

On mac os especially, just opening projectchip in vscode would hold one
CPU spinning at 98% by a cpptools process owned by vscode.
This patch to settings.json excludes the file watcher from endless
recursion via examples/**/third_party/connectedhomeip...

.vscode/settings.json

@@ -117,6 +117,13 @@
         "random": "cpp",
         "thread": "cpp"
     },
+    // Configure paths or glob patterns to exclude from file watching.
+    "files.watcherExclude": {
+        "**/.git/objects/**": true,
+        "**/.git/subtree-cache/**": true,
+        "out/": true,
+        "**/third_party/**": true
+    },
     "files.eol": "\n",
     "editor.formatOnSave": true,
     "better-comments.tags": [