Update rtt-target requirement in /rtic_v0.5/stm32f0_hid_mouse

Updates the requirements on [rtt-target](https://github.com/mvirkkunen/rtt-target) to permit the latest version.
- [Release notes](https://github.com/mvirkkunen/rtt-target/releases)
- [Commits](probe-rs/rtt-target@v0.2.2...v0.3.1)

---
updated-dependencies:
- dependency-name: rtt-target
  dependency-type: direct:production
...

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Author: dependabot[bot]

rtic_v0.5/stm32f0_hid_mouse/Cargo.toml

@@ -12,7 +12,7 @@ branch = "main"
 embedded-hal = "0.2.4"
 usb-device = "0.2.5"
 usbd-hid = "0.4.4"
-rtt-target = { version = "0.2.2", features = ["cortex-m"] }
+rtt-target = { version = "0.3.1", features = ["cortex-m"] }
 panic-halt = "0.2.0"
 panic-rtt-target = { version = "0.1.1", features = ["cortex-m"] }
 cortex-m = "0.7.6"