Update actions/checkout action to v7

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

Author: renovate[bot]

.github/workflows/garm.yml

@@ -30,7 +30,7 @@ jobs:
                 server: [ master ] # [ stable22, stable33, master ]
                 api-level: [ 29 ] # [ 21, 36 ]
         steps:
-            -   uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+            -   uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
             -   name: configure server
                 run: |