web: bump storybook from 7.0.18 to 7.0.20 in /web (#5896)

* web: bump storybook from 7.0.18 to 7.0.20 in /web

Bumps [storybook](https://github.com/storybookjs/storybook/tree/HEAD/code/lib/cli) from 7.0.18 to 7.0.20.
- [Release notes](https://github.com/storybookjs/storybook/releases)
- [Changelog](https://github.com/storybookjs/storybook/blob/v7.0.20/CHANGELOG.md)
- [Commits](https://github.com/storybookjs/storybook/commits/v7.0.20/code/lib/cli)

---
updated-dependencies:
- dependency-name: storybook
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

* web: add storybook theme

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

---------

Signed-off-by: dependabot[bot] <support@github.com>
Signed-off-by: Jens Langhammer <jens@goauthentik.io>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Jens Langhammer <jens@goauthentik.io>

web/.storybook/authentikTheme.ts

@@ -0,0 +1,10 @@
+import { create } from "@storybook/theming/create";
+
+
+export default create({
+    base: "light",
+    brandTitle: "authentik Storybook",
+    brandUrl: "https://goauthentik.io",
+    brandImage: "https://goauthentik.io/img/icon_left_brand_colour.svg",
+    brandTarget: "_self",
+});