fix: remove Flux validation and fix YAML linting

- Remove Flux validation job (repo doesn't contain Flux resources)
- Fix trailing spaces in best-practices workflow
- Add missing newline at end of znc/statefulset.yaml

Flux validates Kustomization CRDs, not plain manifests. Since this
repo only contains the manifests deployed by Flux (not the Flux
resources themselves), the validation doesn't apply.

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

.gitea/workflows/validate.yaml

@@ -93,21 +93,3 @@ jobs:
               -skip HTTPRoute \
               -verbose
           fi
-
-  flux-validate:
-    name: Flux Build Validation
-    runs-on: ubuntu-latest
-    container:
-      image: catthehacker/ubuntu:act-latest
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v4
-
-      - name: Install Flux CLI
-        run: |
-          curl -s https://fluxcd.io/install.sh | bash -s /usr/local/bin
-
-      - name: Validate Flux Kustomization
-        run: |
-          # Use the repository name or 'app' as the kustomization name for validation
-          flux build kustomization irc --path . --dry-run