Update minicbor requirement from 0.7 to 0.8

Updates the requirements on [minicbor](https://gitlab.com/twittner/minicbor) to permit the latest version.
- [Release notes](https://gitlab.com/twittner/minicbor/tags)
- [Changelog](https://gitlab.com/twittner/minicbor/blob/master/CHANGELOG.md)
- [Commits](https://gitlab.com/twittner/minicbor/compare/minicbor-v0.7.0...minicbor-v0.8.0)

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

protocols/request-response/Cargo.toml

@@ -17,7 +17,7 @@ libp2p-core = { version = "0.27.0", path = "../../core" }
 libp2p-swarm = { version = "0.28.0", path = "../../swarm" }
 log = "0.4.11"
 lru = "0.6"
-minicbor = { version = "0.7", features = ["std", "derive"] }
+minicbor = { version = "0.8", features = ["std", "derive"] }
 rand = "0.7"
 smallvec = "1.4"
 unsigned-varint = { version = "0.7", features = ["std", "futures"] }