build(deps): bump chacha20 from 0.10.0-rc.5 to 0.10.0-rc.6

Bumps [chacha20](https://github.com/RustCrypto/stream-ciphers) from 0.10.0-rc.5 to 0.10.0-rc.6.
- [Commits](RustCrypto/stream-ciphers@chacha20-v0.10.0-rc.5...chacha20-v0.10.0-rc.6)

---
updated-dependencies:
- dependency-name: chacha20
  dependency-version: 0.10.0-rc.6
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

Cargo.lock

@@ -21,7 +21,7 @@ rust-version = "1.85"
 
 [dependencies]
 aead = { version = "0.6.0-rc.3", default-features = false }
-chacha20 = { version = "0.10.0-rc.5", default-features = false, features = ["xchacha"] }
+chacha20 = { version = "0.10.0-rc.6", default-features = false, features = ["xchacha"] }
 cipher = "0.5.0-rc.2"
 poly1305 = "0.9.0-rc.3"
 zeroize = { version = "1.8", optional = true, default-features = false }