[MC-266913] Downloading resource pack fails with error when the server responds with Content-Length: 0

When a server responds with Content-Length: 0 during the server resource pack download, the download fails with a division-by-zero error.

[22:25:14] [Download-2/ERROR]: Failed to download http://192.168.0.200:8000/test
java.lang.IllegalStateException: Failed to download file http://192.168.0.200:8000/test
	at aue.a(SourceFile:127) ~[minecraft-1.20.3-pre1-client.jar:?]
	at aor.a(SourceFile:103) ~[minecraft-1.20.3-pre1-client.jar:?]
	at java.util.HashMap.forEach(HashMap.java:1421) ~[?:?]
	at aor.b(SourceFile:99) ~[minecraft-1.20.3-pre1-client.jar:?]
	at aor.c(SourceFile:136) ~[minecraft-1.20.3-pre1-client.jar:?]
	at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1768) ~[?:?]
	at bit.h(SourceFile:91) ~[minecraft-1.20.3-pre1-client.jar:?]
	at bit.a(SourceFile:146) ~[minecraft-1.20.3-pre1-client.jar:?]
	at bit.run(SourceFile:102) ~[minecraft-1.20.3-pre1-client.jar:?]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136) ~[?:?]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635) ~[?:?]
	at java.lang.Thread.run(Thread.java:840) ~[?:?]
Caused by: java.lang.ArithmeticException: / by zero
	at gha$1.b(SourceFile:102) ~[minecraft-1.20.3-pre1-client.jar:?]
	at gha$1.a(SourceFile:121) ~[minecraft-1.20.3-pre1-client.jar:?]
	at aue.a(SourceFile:87) ~[minecraft-1.20.3-pre1-client.jar:?]
	... 11 more