Add reviewdog GitHub action (#337)

* Add reviewdog action

* Reports results as PR review comments

* Run on synchronize

* cleanup triggers

* Use consistent step name

.github/workflows/integration-tests.yml

 name: Test GoShimmer
-on:
-  push:
-  pull_request:
-    types: [opened, reopened]
+
+on: [push, pull_request]
+
 jobs:
 
   integration-test:

.github/workflows/reviewdog.yml

+name: reviewdog
+
+on: pull_request
+
+jobs:
+
+  golangci-lint:
+    name: GolangCI-Lint 
+    runs-on: ubuntu-latest
+    steps:
+
+    - name: Check out code into the Go module directory
+      uses: actions/checkout@v2
+    
+    - name: Run golangci-lint
+      uses: docker://reviewdog/action-golangci-lint:latest
+      with:
+        github_token: ${{ secrets.github_token }}
+        golangci_lint_flags: "--timeout=10m"
+        reporter: "github-pr-review"

.github/workflows/test.yml

 name: Test GoShimmer
-on:
-  push:
-  pull_request:
-    types: [opened, reopened]
+
+on: [push, pull_request]
+
 jobs:
 
   build: