ci: remove GitHub CI — native git.hanzo.ai + cd.hanzo.ai only

This workflow ran on a self-hosted actions-runner-controller pool. ARC is
decommissioned: CI executes inside git.hanzo.ai (Gitea Actions, .hanzo/workflows)
and delivery is cd.hanzo.ai reconciling the reviewed image pin in
hanzoai/universe. GitHub is a mirror and runs nothing.

Removed rather than repointed — there is no GitHub-side pool to move to, and
leaving it would keep ARC load-bearing.

.github/workflows/server-tests-mariadb-faux.yml

@@ -1,24 +0,0 @@
-# Tests are skipped for these files but github doesn't allow "passing" hence this is required.
-
-name: Skipped Tests
-
-on:
-  pull_request:
-    paths:
-      - "**.js"
-      - "**.css"
-      - "**.md"
-      - "**.html"
-
-jobs:
-  test:
-    runs-on: hanzo-build-linux-amd64
-    strategy:
-      matrix:
-        container: [1, 2, 3, 4]
-
-    name: Python Unit Tests
-
-    steps:
-      - name: Pass skipped tests unconditionally
-        run: "echo Skipped"