Add **/.DS_Store to the .gitignore. (#171)

* Add **/.DS_Store to the .gitignore.

* .gitignore: remove redundant double asterisk

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Co-authored-by: Cameron Brown <me@cbrxyz.com>

Author: blahnikkai

.gitignore

@@ -143,3 +143,4 @@ cython_debug/
 
 .vscode
 .idea/
+.DS_Store