fix: throw EntryMissingException for null entries in hash palette

[embeddedt]

At some point (I believe it was 1.17 or 1.18), vanilla changed the default palettes used by PalettedContainers (including BiMapPalette) to throw EntryMissingException if the entry for the desired ID is null. This PR adjusts Lithium to do the same.

[Nolij]

This looks like a fairly straightforward change. Any reason why it hasn't been merged yet?

[2No2Name]

It hasn't been merged yet, because I have been quite busy