Bump the plugin version to 3.9.3 (#545)

Once this gets merged, I will tag it and push, so that the release process starts.

Author: mumoshu

plugin.yaml

@@ -1,7 +1,7 @@
 name: "diff"
 # Version is the version of Helm plus the number of official builds for this
 # plugin
-version: "3.9.2"
+version: "3.9.3"
 usage: "Preview helm upgrade changes as a diff"
 description: "Preview helm upgrade changes as a diff"
 useTunnel: true