chore(deps): bump memcache from 0.20.0 to 0.21.0 (#49)

Bumps [memcache](https://github.com/aisk/rust-memcache) from 0.20.0 to 0.21.0.
- [Release notes](https://github.com/aisk/rust-memcache/releases)
- [Commits](aisk/rust-memcache@v0.20.0...v0.21.0)

---
updated-dependencies:
- dependency-name: memcache
  dependency-version: 0.21.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: NullSablex <244216261+NullSablex@users.noreply.github.com>

Author: dependabot[bot]

Cargo.lock

@@ -10,7 +10,7 @@ crate-type = ["cdylib"]
 
 [dependencies]
 samp = { package = "rust-samp", path = "../../samp", features = ["encoding"] }
-memcache = { version = "0.20", default-features = false }
+memcache = { version = "0.21", default-features = false }
 log = "0.4"
 fern = "0.7"