chore(deps): update actions/checkout action to v3 (#35)

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

Author: renovate[bot]

.github/workflows/merge.yml

@@ -19,7 +19,7 @@ jobs:
       image: ${{ matrix.container }}
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Cache virtualenvironment
         uses: actions/cache@v2

.github/workflows/pullrequest.yml

@@ -22,7 +22,7 @@ jobs:
       image: ${{ matrix.container }}
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Cache virtualenvironment
         uses: actions/cache@v2

.github/workflows/release.yml

@@ -23,7 +23,7 @@ jobs:
       image: ${{ matrix.container }}
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Cache virtualenvironment
         uses: actions/cache@v2