Allow zip files as libraries.

[Dreytac]

While trying to create a modpack with Forge for v1.19, the build fails as Forge provides the _mcpconfig library as a zip file. This causes the builder to fail to download as it doesn't allow zip files as a content type.

[info] Downloading library de.oceanlabs.mcp:mcp_config:1.19.2-20220805.130853@zip from https://maven.minecraftforge.net/de/oceanlabs/mcp/mcp_config/1.19.2-20220805.130853/mcp_config-1.19.2-20220805.130853.zip... [info] Could not get file from https://maven.minecraftforge.net/de/oceanlabs/mcp/mcp_config/1.19.2-20220805.130853/mcp_config-1.19.2-20220805.130853.zip: Did not get expected content type 'application/java-archive | application/octet-stream', instead got 'application/zip'.

[hedgehog1029]

right, yes, I added that as a sanity check recently, but of course the config ZIPs are downloaded via the same mechanism...