chore(deps-dev): bump @storybook/addon-storysource from 6.1.15 to 6.1.18

Bumps [@storybook/addon-storysource](https://github.com/storybookjs/storybook/tree/HEAD/addons/storysource) from 6.1.15 to 6.1.18.
- [Release notes](https://github.com/storybookjs/storybook/releases)
- [Changelog](https://github.com/storybookjs/storybook/blob/next/CHANGELOG.md)
- [Commits](https://github.com/storybookjs/storybook/commits/v6.1.18/addons/storysource)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -67,7 +67,7 @@
     "@storybook/addon-actions": "^6.1.18",
     "@storybook/addon-knobs": "^6.1.18",
     "@storybook/addon-links": "^6.1.18",
-    "@storybook/addon-storysource": "^6.1.15",
+    "@storybook/addon-storysource": "^6.1.18",
     "@storybook/addon-viewport": "^6.1.18",
     "@storybook/addons": "^6.1.18",
     "@storybook/preset-ant-design": "0.0.1",