Rust version of tree-sitter is pinned

[GRA0007]

The rust binding has pinned the version of tree-sitter at 0.20.6, which means the crate gives a mismatched types error if used with a different version of tree-sitter.

tree-sitter-svelte/Cargo.toml

Line 25 in ea528fc

tree-sitter = "0.20.6"

It should provide a range, like >= 0.21, < 0.23.