v6.0.0-alpha.1

Intermediate alpha release for ink!.

This release is compatible with:

• polkadot-sdk commit cb629d46ebf00aa65624013a61f9c69ebf02b0b4
• cargo-contract v6.0.0-alpha.1
• ink-node v0.44.0 (notice there are binary releases linked)
• Passet Hub if no newer pull request has been merged than this one

To depend on this release:

ink = { git = "https://github.com/use-ink/ink", tag = "v6.0.0-alpha.1" }
ink_e2e = { git = "https://github.com/use-ink/ink", tag = "v6.0.0-alpha.1" }