update dependencies

This updates the dependencies to their latest version. No API changes
of these updates impact confy, so no code changes are needed. The
code builds and the tests run.

This closes rust-cli#87.

Cargo.toml

@@ -11,11 +11,11 @@ edition = "2021"
 
 [dependencies]
 ron = { version = "0.8.0", optional = true }
-directories = "4.0"
+directories = "5"
 serde = "^1.0"
-serde_yaml = { version = "0.8", optional = true }
+serde_yaml = { version = "0.9", optional = true }
 thiserror = "1.0"
-toml = { version = "^0.5", optional = true }
+toml = { version = "0.8", optional = true }
 
 [features]
 default = ["toml_conf"]