chore(deps-dev): bump @storybook/addon-a11y

Bumps [@storybook/addon-a11y](https://github.com/storybookjs/storybook/tree/HEAD/addons/a11y) from 6.2.0-rc.4 to 6.2.0-rc.6.
- [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/v6.2.0-rc.6/addons/a11y)

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

package.json

@@ -69,7 +69,7 @@
     "@jetbrains/eslint-config": "^5.3.1",
     "@jetbrains/generator-ring-ui": "^2.0.137",
     "@jetbrains/stylelint-config": "^2.0.1",
-    "@storybook/addon-a11y": "6.2.0-rc.4",
+    "@storybook/addon-a11y": "6.2.0-rc.6",
     "@storybook/addon-docs": "6.2.0-rc.6",
     "@storybook/addon-essentials": "6.2.0-rc.4",
     "@storybook/addon-storyshots": "6.2.0-beta.5",