Bump tokio from 0.2.24 to 0.3.7 in /graph-data.rs

Bumps [tokio](https://github.com/tokio-rs/tokio) from 0.2.24 to 0.3.7.
- [Release notes](https://github.com/tokio-rs/tokio/releases)
- [Commits](tokio-rs/tokio@tokio-0.2.24...tokio-0.3.7)

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

Author: dependabot[bot]

graph-data.rs/Cargo.lock

@@ -6,7 +6,7 @@ edition = "2018"
 
 [dependencies]
 cincinnati = { git = "https://github.com/openshift/cincinnati", rev = "942743910e6fdee387dce99e243dcc52b5cf70bd"}
-tokio = { version = "0.2.11", features = [ "fs", "stream" ] }
+tokio = { version = "0.3.7", features = [ "fs", "stream" ] }
 serde = "^1.0.124"
 serde_yaml = "^0.8.17"
 anyhow = "1.0"