Add working-directory support (#18)

Add working-directory support

Fixes #15

action.yml

@@ -10,9 +10,9 @@ inputs:
     description: 'golangci-lint command line arguments'
     default: ''
     required: false
-  github-token:
-    description: 'GitHub token with scope `repo.public_repo`. Used for fetching a list of releases of golangci-lint.'
-    required: true
+  working-directory:
+    description: 'golangci-lint working directory, default is project root'
+    required: false
 
 runs:
   using: 'node12'
@@ -20,4 +20,4 @@ runs:
   post: 'dist/post_run/index.js'
 branding:
   icon: 'shield'
-  color: 'yellow'
+  color: 'yellow'