[jextract] CodePrinter indentation improvements #460

Job	Run time
Swift tests (swift:6.0.2 jdk:Corretto os:jammy)	4m 55s
Java tests (swift:6.0.2 jdk:Corretto os:jammy)	8m 22s
Verify Samples (swift:6.0.2 jdk:Corretto os:jammy)	17m 45s
soundness / Broken symlinks check	2s
soundness / API breakage check	0s
soundness / Format check	0s
soundness / Documentation check	39s
soundness / License headers check	5s
soundness / Python lint check	7s
soundness / Shell check	32s
soundness / Unacceptable language check	5s
soundness / YAML lint check	4s
	32m 36s

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