ci: Drop differential shellcheck

We already run shellcheck on all scripts as part of the main CI job,
so we don't really get any benefit of a differential shellcheck as all
our code is already checked by shellcheck so let's just drop it.

diff --git a/.github/workflows/differential-shellcheck.yml b/.github/workflows/differential-shellcheck.yml
deleted file mode 100644 (file)
index c3f7036..0000000
--- a/.github/workflows/differential-shellcheck.yml
+++ /dev/null
@@ -1,32 +0,0 @@
----
-# https://github.com/redhat-plumbers-in-action/differential-shellcheck#readme
-
-name: Differential ShellCheck
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - main
-
-permissions:
-  contents: read
-
-jobs:
-  lint:
-    runs-on: ubuntu-24.04
-
-    permissions:
-      security-events: write
-
-    steps:
-      - name: Repository checkout
-        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
-        with:
-          fetch-depth: 0
-
-      - name: Differential ShellCheck
-        uses: redhat-plumbers-in-action/differential-shellcheck@dd551ce780d8af741f8cd8bab6982667b906b457
-        with:
-          token: ${{ secrets.GITHUB_TOKEN }}