Update Cargo.toml

[note89]

I am using this package together with quite a few other tree-sitter libs.

This line makes it so this package cannot be used with other tree-sitter- packages that want 0.21 or newer, like https://github.com/tree-sitter/tree-sitter-rust/blob/master/Cargo.toml#L23 https://github.com/tree-sitter/tree-sitter-cpp/blob/master/Cargo.toml#L23 https://github.com/tree-sitter/tree-sitter-c/blob/master/Cargo.toml#L23 https://github.com/tree-sitter/tree-sitter-php/blob/master/Cargo.toml#L31 https://github.com/tree-sitter/tree-sitter-go/blob/master/Cargo.toml#L23 https://github.com/tree-sitter/tree-sitter-python/blob/master/Cargo.toml#L24

Can we bump this?