[JExtract] Prohibit 'throws' in FFM generator #579

Job	Run time
Java tests (swift:6.0.2 jdk:Corretto os:jammy)	10m 26s
Swift tests (swift:6.0.2 jdk:Corretto os:jammy)	4m 49s
Verify Sample JavaKitSampleApp (swift:6.0.2 jdk:Corretto os:jammy)	4m 23s
Verify Sample JavaProbablyPrime (swift:6.0.2 jdk:Corretto os:jammy)	4m 17s
Verify Sample SwiftKitSampleApp (swift:6.0.2 jdk:Corretto os:jammy)	6m 29s
Verify Sample SwiftAndJavaJarSampleLib (swift:6.0.2 jdk:Corretto os:jammy)	6m 41s
Verify Sample JavaSieve (swift:6.0.2 jdk:Corretto os:jammy)	1m 11s
Verify Sample JavaDependencySampleApp (swift:6.0.2 jdk:Corretto os:jammy)	5m 1s
soundness / Unacceptable language check	6s
soundness / Documentation check	43s
soundness / License headers check	7s
soundness / Broken symlinks check	9s
soundness / Python lint check	11s
soundness / YAML lint check	9s
soundness / Shell check	42s
soundness / Format check	0s
soundness / API breakage check	0s
	45m 24s

Provide feedback