add workflow to generate README.md (cortexproject#188)

Signed-off-by: Tom Hayward <thayward@infoblox.com>

improve CI rules

Signed-off-by: ShuzZzle <niclas.schad@gmail.com>

.github/workflows/lint-test.yml

@@ -2,9 +2,14 @@ name: Lint and Test Charts
 
 on:
   push:
-    branches:
+    branches-ignore:
+      - master
       - main
   pull_request:
+    paths-ignore:
+      - '*.md'
+      - 'docs/**'
+      - 'tools/**'
 
 jobs:
   lint-test:
@@ -35,15 +40,10 @@ jobs:
       - name: Run chart-testing (lint)
         run: ct lint --config ct.yaml
 
-      - name: Updated README.md
-        run: |
-          make README.md
-          git diff --exit-code -- README.md
-
       - name: Create kind cluster
         uses: helm/kind-action@v1.2.0
 
       - name: Run chart-testing (install)
         run: |
           kubectl create namespace cortex
-          ct install --config ct.yaml --namespace cortex
+          ct install --config ct.yaml --namespace cortex

.github/workflows/readme.yml

@@ -0,0 +1,30 @@
+name: Generate README.md
+
+on:
+  push:
+    branches-ignore:
+      - main
+      - master
+    paths:
+      - values.yaml
+
+jobs:
+  generate:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Generate README.md
+        run: |
+          make README.md
+
+      - name: Commit changes
+        uses: EndBug/add-and-commit@v7
+        with:
+          add: README.md
+          default_author: github_actions
+          message: "[skip ci] generate README.md"
+          signoff: true