style(regular_expression): re-order dependencies in Cargo.toml (#6672)

Follow-on after #6404. Nit. Group optional dependencies together.

Author: overlookmotel

crates/oxc_regular_expression/Cargo.toml

@@ -28,9 +28,9 @@ oxc_span = { workspace = true }
 
 phf = { workspace = true, features = ["macros"] }
 rustc-hash = { workspace = true }
-serde = { workspace = true, optional = true }
 unicode-id-start = { workspace = true }
 
+serde = { workspace = true, optional = true }
 wasm-bindgen = { workspace = true, optional = true }
 
 [features]