deps: update home requirement from =0.5.9 to =0.5.12 in /backend

Updates the requirements on [home](https://github.com/rust-lang/cargo) to permit the latest version.
- [Changelog](https://github.com/rust-lang/cargo/blob/master/CHANGELOG.md)
- [Commits](rust-lang/cargo@home-0.5.9...home-0.5.12)

---
updated-dependencies:
- dependency-name: home
  dependency-version: 0.5.12
  dependency-type: direct:production
...

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

Author: dependabot[bot]

backend/Cargo.toml

@@ -39,7 +39,7 @@ subtle = "2.5"
 reqwest = { version = "0.11", features = ["json"] }
 
 [dependencies.home]
-version = "=0.5.9"
+version = "=0.5.12"
 
 [dependencies.base64ct]
 version = "=1.6.0"