Update to tree-sitter 0.21

[rien]

The new tree-sitter 0.21 updated to the newer NAPI api for native modules, which is incompatible with the older API, fortunately someone has created a compatibility layer (https://github.com/segevfiner/node-tree-sitter-compat) so both API's can be used simultaneously.

In order to update to tree-sitter 0.21 we should either:

• Check if we can easily update the old parsers ourselves (creating a temporary fork and upstreaming)
• Check if we can use the compatibility layer if the above is not possible
• Wait until all our parsers have updated themselves

Which of our parsers have not yet updated to 0.21:

• https://github.com/elm-tooling/tree-sitter-elm
• https://github.com/DerekStride/tree-sitter-sql
• https://github.com/tree-sitter/tree-sitter-verilog
• https://github.com/r-lib/tree-sitter-r