Merge pull request 'Update actions/checkout action to v4' (#3) from renovate/actions-checkout-4.x into master

Reviewed-on: https://codeberg.org/subDesTagesMitExtraKaese/matrix-stt-bot/pulls/3

.github/workflows/docker.yml

@@ -12,7 +12,7 @@ jobs:
     steps:
       -
         name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           submodules: recursive
       -