fix Ubuntu CI

.github/workflows/build.yml

@@ -23,12 +23,12 @@ jobs:
     steps:
       # We need a proper Git repository, but the checkout step will unpack a tarball instead of doing a clone
       # if the Git version is less than 2.18.
-      - name: Install a newer version of Git (Linux)
-        if: runner.os == 'Linux'
-        run: |
-          . /etc/os-release
-          echo deb http://deb.debian.org/debian "$VERSION_CODENAME"-backports main >> /etc/apt/sources.list
-          apt-get update && apt-get install -y git/"$VERSION_CODENAME"-backports
+      # - name: Install a newer version of Git (Linux)
+      #   if: runner.os == 'Linux'
+      #   run: |
+      #     . /etc/os-release
+      #     echo deb http://deb.debian.org/debian "$VERSION_CODENAME"-backports main >> /etc/apt/sources.list
+      #     apt-get update && apt-get install -y git/"$VERSION_CODENAME"-backports
       # We set LF endings so that the Windows environment is consistent with Appveyor
       # See here for context: https://github.com/actions/checkout/issues/135
       - name: Set git to use LF
@@ -37,9 +37,8 @@ jobs:
           git config --global core.eol lf
           git config --global core.longpaths true
       - uses: actions/checkout@v2
-      - name: Setup Haskell (macOS and Windows)
-        if: runner.os != 'Linux'
-        uses: haskell/actions/setup@v1
+      - name: Setup Haskell
+        uses: haskell-actions/setup@v2
         with:
           enable-stack: true
           stack-version: "${{ env.STACK_VERSION }}"