Fix: NPM canary releases (#66727)

* fix(packages): remove double trailing slash from npmrc credentials

* chore(packages): add new line to storybook config to trigger an npm canary release

packages/grafana-ui/.storybook/main.ts

@@ -100,6 +100,7 @@ const mainConfig: StorybookConfig = {
       savePropValueAsString: true,
     },
   },
+
   webpackFinal: async (config) => {
     // expose jquery as a global so jquery plugins don't break at runtime.
     config.module?.rules?.push({