Align nested_identifier -> member_expression alias field names

[helixbass]

This PR adds field names to the existing nested_identifier rule (which gets used for dotted JSX element names eg <Foo.Bar />) so that when it gets aliased to $.member_expression it has the same field names as a "normal" member_expression (ie object and property)

This seems desirable to me so that one can treat it as an "invariant" that when you see a member_expression node it definitely has object and property fields

Checklist:

• [x] All tests pass in CI.
• [x] The script/parse-examples passes without issues. (I think? I see Successfully parsed 2615 of 2616 example files (100.0%))
• [x] There are sufficient tests for the new fix/feature.
• [x] Grammar rules have not been renamed unless absolutely necessary.
• [x] The conflicts section hasn't grown too much.
• [x] The parser size hasn't grown too much (check the value of STATE_COUNT in src/parser.c).

[amaanq]

I'm going to assume you're using the node version of tree-sitter to generate - can you use the Rust crate on master? (notice the small changes made to parser.h, that's bad)

[helixbass]

Ok re-ran tree-sitter generate using a locally built version of tree-sitter cli/ with its current master, I see the changes to parser.h went away

[amaanq]

Hi @helixbass, I cherry picked your changes onto #291, thank you!