Need to retry when Fabric website API returns invalid JSON

[itzg]

Observed during itzg/minecraft-server PR testing builds, such as https://github.com/itzg/docker-minecraft-server/actions/runs/14232377500/job/39885487530

me.itzg.helpers.errors.GenericException: Failed to parse response body into list of class me.itzg.helpers.fabric.LoaderResponseEntry: Unexpected end-of-input in VALUE_STRING
 at [Source: REDACTED (`StreamReadFeature.INCLUDE_SOURCE_IN_LOCATION` disabled); line: 15739, column: 44] (through reference chain: java.util.ArrayList[224])
	at me.itzg.helpers.http.ObjectFetchBuilder.lambda$handleResponse$1(ObjectFetchBuilder.java:89)
	at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:132)
	at reactor.core.publisher.MonoPublishOn$PublishOnSubscriber.run(MonoPublishOn.java:181)
	at reactor.core.scheduler.SchedulerTask.call(SchedulerTask.java:68)
	at reactor.core.scheduler.SchedulerTask.call(SchedulerTask.java:28)
	at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
	at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at java.base/java.lang.Thread.run(Unknown Source)
	Suppressed: java.lang.Exception: #block terminated with an error
		at reactor.core.publisher.BlockingSingleSubscriber.blockingGet(BlockingSingleSubscriber.java:104)
		at reactor.core.publisher.Mono.block(Mono.java:1779)
		at me.itzg.helpers.fabric.FabricLauncherInstaller.installUsingVersions(FabricLauncherInstaller.java:71)
		at me.itzg.helpers.fabric.InstallFabricLoaderCommand.call(InstallFabricLoaderCommand.java:93)
		at me.itzg.helpers.fabric.InstallFabricLoaderCommand.call(InstallFabricLoaderCommand.java:15)
		at picocli.CommandLine.executeUserObject(CommandLine.java:2045)
		at picocli.CommandLine.access$1500(CommandLine.java:148)
		at picocli.CommandLine$RunLast.executeUserObjectOfLastSubcommandWithSameParent(CommandLine.java:2465)
		at picocli.CommandLine$RunLast.handle(CommandLine.java:2457)
		at picocli.CommandLine$RunLast.handle(CommandLine.java:2419)
		at picocli.CommandLine$AbstractParseResultHandler.execute(CommandLine.java:2277)
		at picocli.CommandLine$RunLast.execute(CommandLine.java:2421)
		at picocli.CommandLine.execute(CommandLine.java:2174)
		at me.itzg.helpers.McImageHelper.main(McImageHelper.java:178)
Caused by: com.fasterxml.jackson.databind.JsonMappingException: Unexpected end-of-input in VALUE_STRING
 at [Source: REDACTED (`StreamReadFeature.INCLUDE_SOURCE_IN_LOCATION` disabled); line: 15739, column: 44] (through reference chain: java.util.ArrayList[224])
	at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:401)
	at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:372)
	at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer._deserializeFromArray(CollectionDeserializer.java:381)
	at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:246)
	at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:30)
	at com.fasterxml.jackson.databind.deser.DefaultDeserializationContext.readRootValue(DefaultDeserializationContext.java:342)
	at com.fasterxml.jackson.databind.ObjectReader._bindAndClose(ObjectReader.java:2[131](https://github.com/itzg/docker-minecraft-server/actions/runs/14232377500/job/39885487530#step:7:132))
	at com.fasterxml.jackson.databind.ObjectReader.readValue(ObjectReader.java:1501)
	at me.itzg.helpers.http.ObjectFetchBuilder.lambda$handleResponse$1(ObjectFetchBuilder.java:85)
	... 9 common frames omitted
Caused by: com.fasterxml.jackson.core.io.JsonEOFException: Unexpected end-of-input in VALUE_STRING
 at [Source: REDACTED (`StreamReadFeature.INCLUDE_SOURCE_IN_LOCATION` disabled); line: 15739, column: 44]
	at com.fasterxml.jackson.core.base.ParserMinimalBase._reportInvalidEOF(ParserMinimalBase.java:641)
	at com.fasterxml.jackson.core.base.ParserMinimalBase._reportInvalidEOF(ParserMinimalBase.java:622)
	at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._loadMoreGuaranteed(UTF8StreamJsonParser.java:2457)
	at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._skipString(UTF8StreamJsonParser.java:2635)
	at com.fasterxml.jackson.core.json.UTF8StreamJsonParser.nextToken(UTF8StreamJsonParser.java:714)
	at com.fasterxml.jackson.core.base.ParserMinimalBase.skipChildren(ParserMinimalBase.java:297)
	at com.fasterxml.jackson.databind.DeserializationContext.handleUnknownProperty(DeserializationContext.java:1148)
	at com.fasterxml.jackson.databind.deser.std.StdDeserializer.handleUnknownProperty(StdDeserializer.java:2245)
	at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.handleUnknownProperty(BeanDeserializerBase.java:1821)
	at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.handleUnknownVanilla(BeanDeserializerBase.java:1799)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.vanillaDeserialize(BeanDeserializer.java:316)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:177)
	at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer._deserializeFromArray(CollectionDeserializer.java:361)
	... 15 common frames omitted