Derive `Ord` and `PartialOrd` for `ClassName` #2904

Job	Run time
clippy	1m 45s
license-guard	29s
doc-lints	41s
godot-itest (macos)	55s
godot-itest (windows)	2m 57s
run-examples	1m 20s
godot-itest (linux-full)	2m 28s
rustfmt	13s
unit-test	2m 26s
godot-itest (linux-features-experimental)	2m 20s
godot-itest (linux-4.1)	1m 38s
godot-itest (linux-4.2)	1m 17s
godot-itest (linux-memcheck)	2m 20s
ci-status	1s
	20m 50s

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