Remove go.work file from committed setup.

Reason: the `upgrade-provider` tool updates `provider/go.mod` but doesn't update the `go.work` file. Without `go work use` command, these go out of sync resulting in a build failure.
User should create a local file manually if it is needed by e.g. VSCode

Author: ringods

.gitignore

@@ -23,4 +23,4 @@ provider/**/schema-embed.json
 **/dist
 server
 
-go.work.sum
+go.work*