Bump rocket from 0.4.5 to 0.4.7 in /assets/dockerfiles/base/rust

Bumps [rocket](https://github.com/SergioBenitez/Rocket) from 0.4.5 to 0.4.7.
- [Release notes](https://github.com/SergioBenitez/Rocket/releases)
- [Changelog](https://github.com/SergioBenitez/Rocket/blob/master/CHANGELOG.md)
- [Commits](https://github.com/SergioBenitez/Rocket/compare/v0.4.5...v0.4.7)

---
updated-dependencies:
- dependency-name: rocket
  dependency-type: direct:production
...

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

assets/dockerfiles/base/rust/Cargo.toml

@@ -5,7 +5,7 @@ authors = ["FrontMage <xbgxwh@outlook.com>"]
 edition = "2018"
 
 [dependencies]
-rocket = "0.4.5"
+rocket = "0.4.7"
 rocket_contrib = "0.4.5"
 serde_json = "1.0"
 serde_derive = "1.0.70"