Better CI pattern

Author: AlistairB

.github/workflows/ci.yml renamed to .github/workflows/debian.yml

@@ -1,12 +1,12 @@
-name: Validate Docker
+name: Validate Debian
 
 on:
   pull_request:
     branches:
       - master
     paths:
-      - '**/Dockerfile'
-      - '.github/workflows/**'
+      - '**/buster/Dockerfile'
+      - '.github/workflows/debian.yml'
 
 jobs:
   build-smoke-test:
@@ -38,19 +38,12 @@ jobs:
               ${{ matrix.ghc_minor }}/${{ matrix.deb }}
       - uses: actions/checkout@v2
         with:
-          repository: docker-library/official-images
+          repository: AlistairB/official-images
+          ref: haskell-sh
           path: official-images
       - name: run official-images tests
         run: ./official-images/test/run.sh haskell:${{ matrix.ghc }}-${{ matrix.deb }}
 
-  hadolint:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - uses: hadolint/[email protected]
-      with:
-        recursive: true
-
   emulated-architecture-tests:
     timeout-minutes: 60
     runs-on: ubuntu-latest

.github/workflows/lint.yml

@@ -0,0 +1,18 @@
+name: Hadolint
+
+on:
+  pull_request:
+    branches:
+      - master
+    paths:
+      - '**/Dockerfile'
+      - '.github/workflows/lint.yml'
+
+jobs:
+  hadolint:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: hadolint/[email protected]
+      with:
+        recursive: true

.hadolint.yaml

@@ -2,6 +2,7 @@ ignored:
   # https://github.com/hadolint/hadolint/wiki/DL3008
   # Don't want to micro manage the dependency versions.
   - DL3008
+  - DL3018
   # https://github.com/hadolint/hadolint/wiki/DL3003
   # Using cd /tmp is a very convenient way to clean up after a step.
   - DL3003