GH Actions: Removed contents write permission

Hoping that pull-requests is enough and removing contents
limits access to other things (like releases).

Signed-off-by: Ole Herman Schumacher Elgesem <ole@northern.tech>

Author: olehermanse

.github/workflows/update-dep-tables.yml

@@ -11,7 +11,6 @@ jobs:
     name: Update dependency tables
     runs-on: ubuntu-24.04
     permissions:
-      contents: write
       pull-requests: write
     steps:
       - name: Checks-out repository

.github/workflows/update-deps.yml

@@ -16,7 +16,6 @@ jobs:
     name: Update dependencies
     runs-on: ubuntu-latest
     permissions:
-      contents: write
       pull-requests: write
     strategy:
       matrix: