Update dependency rack to v3.1.16 (#617)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [rack](https://redirect.github.com/rack/rack)
([changelog](https://redirect.github.com/rack/rack/blob/main/CHANGELOG.md))
| `3.1.15` -> `3.1.16` |
[![age](https://developer.mend.io/api/mc/badges/age/rubygems/rack/3.1.16?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/rubygems/rack/3.1.16?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/rubygems/rack/3.1.15/3.1.16?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/rubygems/rack/3.1.15/3.1.16?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>rack/rack (rack)</summary>

###
[`v3.1.16`](https://redirect.github.com/rack/rack/compare/v3.1.15...v3.1.16)

[Compare
Source](https://redirect.github.com/rack/rack/compare/v3.1.15...v3.1.16)

</details>

---

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Gemfile.lock

@@ -58,7 +58,7 @@ GEM
     prism (1.4.0)
     public_suffix (6.0.1)
     racc (1.8.1)
-    rack (3.1.15)
+    rack (3.1.16)
     rackup (2.2.1)
       rack (>= 3)
     rainbow (3.1.1)