fix(ci): Use correct nameing for github token (#82)

Signed-off-by: Alexander Dahmen <alexander.dahmen@inovex.de>

Author: Fyusel

.github/workflows/check-upgrade-provider.yaml

@@ -1,5 +1,5 @@
 env:
-  GH_TOKEN: ${{ secrets.GH_TOKEN }}
+  GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 jobs:
   upgrade_provider:
     name: upgrade-provider

.github/workflows/upgrade-provider.yaml

@@ -1,5 +1,5 @@
 env:
-  GH_TOKEN: ${{ secrets.GH_TOKEN }}
+  GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 jobs:
   upgrade_provider:
     if: ${{ (contains(github.event.issue.title, 'Upgrade terraform-provider-')) || github.event_name == 'workflow_dispatch' }}