Bump generic-array in /examples/signaling-server-rust

Bumps [generic-array](https://github.com/fizyk20/generic-array) from 0.12.3 to 0.12.4.
- [Release notes](https://github.com/fizyk20/generic-array/releases)
- [Changelog](https://github.com/fizyk20/generic-array/blob/0.12.4/CHANGELOG.md)
- [Commits](https://github.com/fizyk20/generic-array/compare/0.12.3...0.12.4)

---
updated-dependencies:
- dependency-name: generic-array
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>

examples/signaling-server-rust/Cargo.lock

@@ -1,5 +1,7 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
+version = 3
+
 [[package]]
 name = "arc-swap"
 version = "0.4.7"
@@ -240,9 +242,9 @@ dependencies = [
 
 [[package]]
 name = "generic-array"
-version = "0.12.3"
+version = "0.12.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c68f0274ae0e023facc3c97b2e00f076be70e254bc851d972503b328db79b2ec"
+checksum = "ffdf9f34f1447443d37393cc6c2b8313aebddcd96906caf34e54c68d8e57d7bd"
 dependencies = [
  "typenum",
 ]