Merge pull request #53 from rust-bio/dependabot/cargo/petgraph-0.6.3

chore: Bump petgraph from 0.6.0 to 0.6.3

Author: dlaehnemann

Cargo.lock

@@ -22,5 +22,5 @@ thiserror = "1"
 regex = "1.0"
 lazy_static = "1.1"
 derive-new = "0.5"
-petgraph = { version = ">=0.5,<0.7", optional = true }
+petgraph = { version = ">=0.5, <0.7", optional = true }
 strum_macros = ">=0.20, <0.25"