chore: release v0.6.21 (#528)

## 🤖 New release
* `roadster`: 0.6.20 -> 0.6.21 (✓ API compatible changes)

<details><summary><i><b>Changelog</b></i></summary><p>

<blockquote>

##
[0.6.21](roadster-v0.6.20...roadster-v0.6.21)
- 2024-12-01

### Other

- Update OTEL patch version and remove a deprecated fn call
([#527](#527))
- Update Loco comparisons and add some links to other sections
([#522](#522))
- Add mailpit to SMTP dev server examples
([#521](#521))
- *(deps)* bump codecov/codecov-action from 4 to 5
([#517](#517))
- Upgrade otel/tracing dependencies
([#516](#516))
</blockquote>


</p></details>

---
This PR was generated with
[release-plz](https://github.com/release-plz/release-plz/).

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

CHANGELOG.md

@@ -7,6 +7,16 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.6.21](https://github.com/roadster-rs/roadster/compare/roadster-v0.6.20...roadster-v0.6.21) - 2024-12-01
+
+### Other
+
+- Update OTEL patch version and remove a deprecated fn call ([#527](https://github.com/roadster-rs/roadster/pull/527))
+- Update Loco comparisons and add some links to other sections ([#522](https://github.com/roadster-rs/roadster/pull/522))
+- Add mailpit to SMTP dev server examples ([#521](https://github.com/roadster-rs/roadster/pull/521))
+- *(deps)* bump codecov/codecov-action from 4 to 5 ([#517](https://github.com/roadster-rs/roadster/pull/517))
+- Upgrade otel/tracing dependencies ([#516](https://github.com/roadster-rs/roadster/pull/516))
+
 ## [0.6.20](https://github.com/roadster-rs/roadster/compare/roadster-v0.6.19...roadster-v0.6.20) - 2024-11-17
 
 ### Added

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "roadster"
-version = "0.6.20"
+version = "0.6.21"
 edition = "2021"
 publish = true
 description = "A \"Batteries Included\" web framework for rust designed to get you moving fast."