Invalid conversion to uBO syntax - `[$path]`

[Alex-302]

Matching "the main page only" [$path] should be converted to :matches-path(/^/$/)
uBO's example: https://github.com/gorhill/ublock/wiki/Procedural-cosmetic-filters#subjectmatches-patharg:~:text=%3Amatches%2Dpath(/%5E/%24/)

Original

[$path]fontanka.ru#?#.gridContainer > div[class*="grid"]:has(> section[class^="baseBlock_"] > a[href]:contains(/^(Новости компаний|Фонтанка PRO)$/))

Converted to uBO:

fontanka.ru#?#:matches-path(/^/$/) .gridContainer > div[class*="grid"]:has(> section[class^="baseBlock_"] > a[href]:contains(/^(Новости компаний|Фонтанка PRO)$/))