Split git tag and github release options (#680)

* Split git tag and github release options

* Rename to push-git-tags

* Validate inputs

publish/action.yml

@@ -18,6 +18,12 @@ inputs:
     description: "Whether to create Github releases after publish"
     required: false
     default: true
+  push-git-tags:
+    description: >
+      Whether to create git tags after publish. If `create-github-releases` is set to `true`,
+      this option will also always be `true`.
+    required: false
+    default: true
 outputs:
   published:
     description: "A boolean value to indicate whether a publishing has happened or not"