docs(api.md): Working link to Linux differences (#4232)
docs(api.md): Working link to Linux differences (#4232)

A link on line 525 is pointing to a undefined branch (`lkcr`) in `chromium.googlesource.com/chromium/src/`. Change it to point to `lkgr` instead, since it's the closest defined branch in name.
GoogleChrome/puppeteer,GoogleChrome/puppeteer,puppeteer/puppeteer,puppeteer/puppeteer,puppeteer/puppeteer,puppeteer/puppeteer,GoogleChrome/puppeteer