Update Rust crate enum-map to 2.4.2

Author: renovate[bot]

Cargo.lock

@@ -32,7 +32,7 @@ chrono = "0.4"
 clap = {version = "2", features = ["wrap_help"]}
 download = {path = "download", default-features = false}
 effective-limits = "0.5.3"
-enum-map = "2.0.3"
+enum-map = "2.4.2"
 flate2 = "1"
 git-testament = "0.2"
 home = "0.5.4"