Auto merge of #28525 - teymour-aldridge:gitignore, r=jdm

Remove `settings.json` from `.gitignore`.

Also add `Brewfile.lock.json` to the list of ignored files.

Signed-off-by: teymour-aldridge <teymour.aldridge@icloud.com>

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.gitignore

@@ -41,6 +41,7 @@ capture_webrender/
 # VSCode
 .vscode
 !/.vscode/extensions.json
+!/.vscode/settings.json
 
 # Emacs
 *~
@@ -67,3 +68,6 @@ support/hololens/.vs/
 
 # Layout debugger trace files
 layout_trace*
+
+# Package managers
+etc/taskcluster/macos/Brewfile.lock.json