servo: Merge #14143 - Remove the mingw git to fix AppVeyor builds (from larsbergstrom:git_fix_appveyor); r=notriddle

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Fixes #13939. This is a test, based on @UK992's comment here:
https://github.com/servo/servo/issues/13939#issuecomment-259252852

Please wait for the AppVeyor build to succeed before r+ :-)

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- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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Source-Repo: https://github.com/servo/servo
Source-Revision: 3b298564e126992f8301980b7213495416da60d1

servo/appveyor.yml

@@ -50,7 +50,7 @@ install:
   - if %BUILD_ENV%==gnu  set MSYS=winsymlinks=lnk
   - if %BUILD_ENV%==gnu  bash -lc "echo $MSYSTEM; pacman --needed --noconfirm -Sy pacman-mirrors"
   - if %BUILD_ENV%==gnu  bash -lc "pacman --noconfirm -Sy"
-  - if %BUILD_ENV%==gnu  bash -lc "pacman -Sy --needed --noconfirm git mingw-w64-x86_64-toolchain mingw-w64-x86_64-freetype mingw-w64-x86_64-icu mingw-w64-x86_64-nspr mingw-w64-x86_64-ca-certificates mingw-w64-x86_64-expat mingw-w64-x86_64-cmake tar diffutils patch patchutils make python2-setuptools mingw-w64-x86_64-ffmpeg"
+  - if %BUILD_ENV%==gnu  bash -lc "pacman -Sy --needed --noconfirm mingw-w64-x86_64-toolchain mingw-w64-x86_64-freetype mingw-w64-x86_64-icu mingw-w64-x86_64-nspr mingw-w64-x86_64-ca-certificates mingw-w64-x86_64-expat mingw-w64-x86_64-cmake tar diffutils patch patchutils make python2-setuptools mingw-w64-x86_64-ffmpeg"
   - if %BUILD_ENV%==gnu  bash -lc "easy_install-2.7 pip virtualenv"
   - if %BUILD_ENV%==gnu  bash -lc "mv /mingw64/bin/python2.exe /mingw64/bin/python2-mingw64.exe"
   - if %BUILD_ENV%==gnu  bash -lc "mv /mingw64/bin/python2.7.exe /mingw64/bin/python2.7-mingw64.exe"