CI: replace actions/checkout@v1 with actions/checkout@v2

Author: Lukas Hutak

.github/workflows/main.yml

@@ -20,7 +20,7 @@ jobs:
     name: Build on ${{ matrix.image }}
     container: ${{ matrix.image }}
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
 
     # Dependencies ---------------------------------------------------------------------------
     - name: Install dependencies for libfds and IPFIXcol2 (Ubuntu/Debian)

.github/workflows/packages.yml

@@ -22,7 +22,7 @@ jobs:
     container: ${{ matrix.image }}
 
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - name: Define global variables
       run: echo "::set-output name=zip_file::ipfixcol2-${IMAGE//:/}-$GITHUB_SHA.zip"
       shell: bash
@@ -91,7 +91,7 @@ jobs:
     container: ${{ matrix.image }}
 
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - name: Prepare environment and variables
       run: |
         echo "::set-output name=zip_file::ipfixcol2-${IMAGE//:/}-$GITHUB_SHA.zip"