remove Bracket Pair Colorizer recommendation (#14816)

As of v1.60, vscode has a much faster built-in method of colorizing bracket pairs, making the extension unnecessary.
https://code.visualstudio.com/blogs/2021/09/29/bracket-pair-colorization

.vscode/extensions.json

@@ -5,7 +5,6 @@
     "xaver.clang-format",
     "ms-vscode.cpptools",
     "bierner.github-markdown-preview",
-    "donjayamanne.git-extension-pack",
-    "CoenraadS.bracket-pair-colorizer-2"
+    "donjayamanne.git-extension-pack"
   ]
 }