Update actions/checkout action to v4 (#261)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/build.yml

@@ -70,7 +70,7 @@ jobs:
         brew services start mongodb-community@${{matrix.mongodb}}
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
 
     - name: Setup dotnet SDK
       uses: actions/setup-dotnet@v3
@@ -98,7 +98,7 @@ jobs:
     needs: build
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
     - name: Download coverage reports
       uses: actions/download-artifact@v3
     - name: Install ReportGenerator tool