fix textplots dependency

there is a bug in version 0.8 in drawing step functions, should switch to official release once loony-bean/textplots-rs#58 is merged

Author: rkuhn

topology-checker/Cargo.toml

@@ -15,4 +15,4 @@ rand = "0.9.0"
 serde = { version = "1.0", features = ["derive"] }
 serde_yaml = "0.9"
 terminal_size = "0.4.1"
-textplots = { version = "0.8.6", path = "../../textplots-rs" }
+textplots = { version = "0.8.6", git = "https://github.com/rkuhn/textplots-rs.git" }