Initial checkout action

.forgejo/workflows/test_workflow.yml

@@ -0,0 +1,10 @@
+on:
+  push:
+jobs:
+  test:
+    runs-on: docker
+    container:
+      image: git.hswro.org/fleg/actions-experiments:latest
+    steps:
+      - uses: codeberg.org/fleg/light-actions/checkout@v1
+      - run: cat README

checkout/action.yml

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+name: checkout
+description: Checkout the git repository.
+runs:
+  using: composite
+  steps:
+    - run: |
+        set -eu
+        if ! command -v bash >/dev/null; then
+          printf 'Bash is needed to use this action.'
+          exit 1
+        fi
+        if ! command -v git >/dev/null; then
+          printf 'Git is needed to use this action.'
+          exit 1
+        fi
+      shell: sh
+    - run: |
+        set -eu
+        git init
+        git remote add origin "${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}"
+        git fetch --no-tags --prune --no-recurse-submodules --depth=1 origin "+${GITHUB_SHA}:${GITHUB_REF}"
+        git checkout --force "${GITHUB_REF}"
+      shell: bash