impl: Update dependency webrick to v1.9.0 (#1229)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [webrick](https://redirect.github.com/ruby/webrick) | `1.8.2` ->
`1.9.0` |
[![age](https://developer.mend.io/api/mc/badges/age/rubygems/webrick/1.9.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/rubygems/webrick/1.9.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/rubygems/webrick/1.8.2/1.9.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/rubygems/webrick/1.8.2/1.9.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>ruby/webrick (webrick)</summary>

###
[`v1.9.0`](https://redirect.github.com/ruby/webrick/releases/tag/v1.9.0)

[Compare
Source](https://redirect.github.com/ruby/webrick/compare/v1.8.2...v1.9.0)

#### What's Changed

- Be clear in README that webrick should not be used in production by
[@&#8203;jeremyevans](https://redirect.github.com/jeremyevans) in
[https://github.com/ruby/webrick/pull/149](https://redirect.github.com/ruby/webrick/pull/149)
- Add RBS files by [@&#8203;znz](https://redirect.github.com/znz) in
[https://github.com/ruby/webrick/pull/151](https://redirect.github.com/ruby/webrick/pull/151)
- Prepare new release by [@&#8203;znz](https://redirect.github.com/znz)
in
[https://github.com/ruby/webrick/pull/153](https://redirect.github.com/ruby/webrick/pull/153)

#### New Contributors

- [@&#8203;znz](https://redirect.github.com/znz) made their first
contribution in
[https://github.com/ruby/webrick/pull/151](https://redirect.github.com/ruby/webrick/pull/151)

**Full Changelog**:
ruby/webrick@v1.8.2...v1.9.0

</details>

---

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---

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---

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Signed-off-by: Mend Renovate <[email protected]>

docs/Gemfile.lock

@@ -259,7 +259,7 @@ GEM
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
     unicode-display_width (1.8.0)
-    webrick (1.8.2)
+    webrick (1.9.0)
 
 PLATFORMS
   ruby