script/parse-examples is either broken or not useful

`npm run test` confused me when I tried to run it locally:

> Successfully parsed 0 of 1 example files (0.0%)

I thought it got broken due to a change I introduced, but it seems like master also exhibits this failure:

https://github.com/tree-sitter/tree-sitter-rust/runs/4725533586?check_suite_focus=true#step:5:136