[MC-173067] NullPointerException when a structure containing a campfire is placed during world generation

When a structure:

Contains a campfire
The campfire is placed where a fluid was previously
During world generation (does NOT occur by placing the structure with a structure block)

Then the following crash occurs:

java.lang.NullPointerException: Feature placement
	at bwo.f(SourceFile:201)
	at bpr.a(SourceFile:181)
	at cms.a(SourceFile:280)
	at clx.a(SourceFile:62)
	at clq$a.a(SourceFile:139)
	at clv.a(SourceFile:63)
	at cfl.a(SourceFile:78)
	at cdc.a(SourceFile:53)
	at cka.a(SourceFile:91)
	at java.util.stream.Streams$StreamBuilderImpl.forEachRemaining(Streams.java:419)
	at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:647)
	at cka.a(SourceFile:90)
	at cjj.a(SourceFile:36)
	at cdi.a(SourceFile:21)
	at cdi.a(SourceFile:14)
	at cdc.a(SourceFile:53)
	at bkt.a(SourceFile:417)
	at caa.a(SourceFile:125)
	at cae.c(SourceFile:84)
	at cae.a(SourceFile:214)
	at wp.a(SourceFile:549)
	at com.mojang.datafixers.util.Either$Left.map(Either.java:38)
	at wp.a(SourceFile:543)
	at java.util.concurrent.CompletableFuture.uniCompose(CompletableFuture.java:966)
	at java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:940)
	at java.util.concurrent.CompletableFuture$Completion.run(CompletableFuture.java:456)
	at wr.b(SourceFile:58)
	at aiv.e(SourceFile:83)
	at aiv.a(SourceFile:123)
	at aiv.run(SourceFile:91)
	at java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1402)
	at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
	at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
	at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
	at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)

Steps to reproduce:

Create a new world with default world generation settings
Install the attached datapack, which adds some campfires to the "minecraft:shipwreck/with_mast" structure. Don't forget to /reload.
Search for shipwrecks. Note that it may take a few attempts as not all shipwrecks use the with_mast template, and not all shipwrecks generate underwater.