pw_ide: Replace vscode-gnformat recommendation with gnls

Replace the vscode-gnformat VS Code extension recommendation
with the GN Language Server exension provided by Microsoft.
GN Language Server includes code formatting support in addition
to many intellisense features, and it is actively maintained.

Change-Id: I117c2135d1e452e239072e5960df86cbc4c2026d
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/111750
Reviewed-by: Chad Norvell <chadnorvell@google.com>
Commit-Queue: Ben Lawson <benlawson@google.com>

.vscode/extensions.json

@@ -3,11 +3,12 @@
     "llvm-vs-code-extensions.vscode-clangd",
     "ms-python.python",
     "npclaudiu.vscode-gn",
-    "persidskiy.vscode-gnformat",
+    "msedge-dev.gnls",
     "zxh404.vscode-proto3",
     "josetr.cmake-language-support-vscode"
   ],
   "unwantedRecommendations": [
-    "ms-vscode.cpptools"
+    "ms-vscode.cpptools",
+    "persidskiy.vscode-gnformat",
   ]
 }

.vscode/settings.json

@@ -75,7 +75,7 @@
 
     // Build systems settings
     "[gn]": {
-      "editor.defaultFormatter": "persidskiy.vscode-gnformat"
+      "editor.defaultFormatter": "msedge-dev.gnls"
     },
 
     // C/C++ settings