cargo: bump the patch group in /src/exercises/bare-metal/rtc with 2 updates (#2728)

Bumps the patch group in /src/exercises/bare-metal/rtc with 2 updates:
[chrono](https://github.com/chronotope/chrono) and
[cc](https://github.com/rust-lang/cc-rs).

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

src/exercises/bare-metal/rtc/Cargo.lock

@@ -9,10 +9,10 @@ publish = false
 [dependencies]
 arm-gic = "0.2.2"
 bitflags = "2.9.0"
-chrono = { version = "0.4.40", default-features = false }
+chrono = { version = "0.4.41", default-features = false }
 log = "0.4.27"
 smccc = "0.2.0"
 spin = "0.10.0"
 
 [build-dependencies]
-cc = "1.2.17"
+cc = "1.2.20"