try to fix the git push frogejo action

.forgejo/workflows/update_nix_flakes.yml

@@ -2,7 +2,7 @@ name: Update Nix flakes and commit changes
 
 on:
   schedule:
-    - cron: "40 10 * * *" # not to frequent, GitHub only allows a few pulls per hour
+    - cron: "10 11 * * *" # not to frequent, GitHub only allows a few pulls per hour
 
 jobs:
   update-and-commit:
@@ -39,7 +39,7 @@ jobs:
 
           nix flake update
           
-          export GITHUB_TOKEN=""
+          export GIT_SSH_COMMAND="ssh -i .ssh_key -F /dev/null" 
           
           git diff --quiet && \
           git diff --staged --quiet || \