Revert "ci: add myself as a reviewer on anything in maintainers that's otherwise not maintained" (#437175)

Everyone was right. It is too many notifications and there is too little time to attend to them.

ci/OWNERS

···
 /.github/workflows                      @NixOS/nixpkgs-ci
 /ci                                     @NixOS/nixpkgs-ci
 /ci/OWNERS                              @infinisil @philiptaron
-/maintainers                            @philiptaron
 
 # Development support
 /.editorconfig @Mic92 @zowoq