(maint) Allow git to use long paths in GitHub Actions

Due to unknown environment changes in GitHub Actions runners, we
encountered the following error:
`fatal: cannot create directory: Filename too long`

This commit allows git to use long paths in our GitHub Actions
workflows.

Author: luchihoratiu

.github/workflows/daily_unit_tests_with_nightly_puppet_gem.yaml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   daily_unit_tests_with_nightly_puppet_gem:
-    name: ${{ matrix.os_type }} / Puppet${{ matrix.puppet_version }} gem / Ruby ${{ matrix.ruby }} 
+    name: ${{ matrix.os_type }} / Puppet${{ matrix.puppet_version }} gem / Ruby ${{ matrix.ruby }}
     strategy:
       matrix:
         os: [ 'ubuntu-18.04', 'macos-10.15', 'windows-2016' ]
@@ -50,6 +50,7 @@ jobs:
 
       - name: Prepare testing environment with bundler
         run: |
+          git config --global core.longpaths true
           bundle config set system 'true'
           ${{ matrix.env_set_cmd }}PUPPET_GEM_VERSION=$(ruby -e 'puts /puppet\s+\((.+)\)/.match(`gem list -eld puppet`)[1]')
           bundle update --jobs 4 --retry 3

.github/workflows/static_code_analysis.yaml

@@ -28,7 +28,9 @@ jobs:
           ruby-version: ${{ env.ruby_version }}
 
       - name: Prepare testing environment with bundler
-        run: bundle update --jobs 4 --retry 3
+        run: |
+          git config --global core.longpaths true
+          bundle update --jobs 4 --retry 3
 
       - name: Run commits check
         run: bundle exec rake commits

.github/workflows/unit_tests_with_nightly_puppet_gem.yaml

@@ -52,6 +52,7 @@ jobs:
 
       - name: Prepare testing environment with bundler
         run: |
+          git config --global core.longpaths true
           bundle config set system 'true'
           ${{ matrix.env_set_cmd }}PUPPET_GEM_VERSION=$(ruby -e 'puts /puppet\s+\((.+)\)/.match(`gem list -eld puppet`)[1]')
           bundle update --jobs 4 --retry 3

.github/workflows/unit_tests_with_released_puppet_gem.yaml

@@ -9,7 +9,7 @@ on:
 
 jobs:
   unit_tests_with_released_puppet_gem:
-    name: ${{ matrix.os_type }} / Puppet${{ matrix.puppet_version }} gem / Ruby ${{ matrix.ruby }} 
+    name: ${{ matrix.os_type }} / Puppet${{ matrix.puppet_version }} gem / Ruby ${{ matrix.ruby }}
     strategy:
       matrix:
         os: [ 'ubuntu-18.04', 'macos-10.15', 'windows-2016' ]
@@ -41,6 +41,7 @@ jobs:
 
       - name: Prepare testing environment with bundler
         run: |
+          git config --global core.longpaths true
           bundle config set system 'true'
           bundle update --jobs 4 --retry 3