Bump blosc2-rs -> 0.4.0+2.15.2 and update default features

[milesgranger]

• Bump version 0.6.0 -> 0.7.0
• Bump blosc2-rs -> 0.4.0+2.15.2
• Remove blosc2, igzip, ideflate, izlib from default features
• Remove WASM32 build, breaks every time versions in up streams are changed it seems.

[musicinmybrain]

Since blosc2, igzip, ideflate, and izlib are no longer in the default features, and the Python cramjam doesn’t seem to need them, I might be able to patch out the features requiring blosc2-rs and isal-rs from rust-libcramjam in Fedora and stop worrying about maintaining those in Fedora.

That means I would not be running the tests for those features on various architectures and reporting issues upstream, but on the other hand it would save me a lot of work and no small amount of frustration.

Can I assume that you plan to make the 0.7.0 release soon?

[milesgranger]

Done. I plan to release the next python cramjam using it a bit later when I have some more time. Thanks for your patience with me. :)