niri-config: Add pretty-assertions to tests

The config parse test is pretty big and it's impossible to tell the
difference from the normal assert.

niri-config/Cargo.toml

@@ -17,3 +17,6 @@ regex = "1.10.5"
 smithay = { workspace = true, features = ["backend_libinput"] }
 tracing.workspace = true
 tracy-client.workspace = true
+
+[dev-dependencies]
+pretty_assertions = "1.4.0"

niri-config/src/lib.rs

@@ -2320,6 +2320,8 @@ pub fn set_miette_hook() -> Result<(), miette::InstallError> {
 
 #[cfg(test)]
 mod tests {
+    use pretty_assertions::assert_eq;
+
     use super::*;
 
     #[track_caller]