Update axum-core requirement from 0.4 to 0.5

Updates the requirements on [axum-core](https://github.com/tokio-rs/axum) to permit the latest version.
- [Release notes](https://github.com/tokio-rs/axum/releases)
- [Changelog](https://github.com/tokio-rs/axum/blob/main/CHANGELOG.md)
- [Commits](tokio-rs/axum@axum-core-v0.4.0...axum-core-v0.5.0)

---
updated-dependencies:
- dependency-name: axum-core
  dependency-type: direct:production
...

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

askama_axum/Cargo.toml

@@ -15,7 +15,7 @@ readme = "README.md"
 
 [dependencies]
 askama = { version = "0.13", path = "../askama", default-features = false, features = ["with-axum"] }
-axum-core = "0.4"
+axum-core = "0.5"
 http = "1.0"
 
 [dev-dependencies]