Update lib file name

EndBug · EndBug · commit 6a75638ec3d3 · 2020-03-20T14:51:31.000+01:00
diff --git a/action.yml b/action.yml
@@ -31,7 +31,7 @@ inputs:
 
 runs:
   using: node12
-  main: lib/main.js
+  main: lib/index.js
 
 branding:
   icon: git-commit
