fixes CI (#19)

* Rename workflow from lint to ci

Signed-off-by: Friedrich Gonzalez <friedrichg@gmail.com>

* Run on push and pull_requests for main

Signed-off-by: Friedrich Gonzalez <friedrichg@gmail.com>

* Use ubuntu-latest

Signed-off-by: Friedrich Gonzalez <friedrichg@gmail.com>

---------

Signed-off-by: Friedrich Gonzalez <friedrichg@gmail.com>

Author: friedrichg

.github/workflows/lint.yaml renamed to .github/workflows/ci.yaml

@@ -1,11 +1,14 @@
 name: CI
 
 on:
+  push:
+    branches: [ main ]
   pull_request:
+    branches: [ main ]
 
 jobs:
   lint:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     container: quay.io/cortexproject/cortex-jsonnet-build-image:c924d52
     steps:
       - uses: actions/checkout@v2
@@ -19,7 +22,7 @@ jobs:
       - name: "Lint playbooks"
         run: make lint-playbooks
   build:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     container: quay.io/cortexproject/cortex-jsonnet-build-image:c924d52
     steps:
       - uses: actions/checkout@v2
@@ -30,7 +33,7 @@ jobs:
       - name: "Build mixin"
         run: make build-mixin
   readme:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     container: quay.io/cortexproject/cortex-jsonnet-build-image:c924d52
     steps:
       - uses: actions/checkout@v2
@@ -39,4 +42,4 @@ jobs:
           fetch-depth: 0
 
       - name: "Test readme"
-        run: make test-readme    
+        run: make test-readme