[README.md] Update reference to cookie export extension for Chrome (closes #26885...

[README.md] Update reference to cookie export extension for Chrome (closes #26885) (#27433)

The cookies.txt extension doesn't exist anymore on the Chrome Web Store (see https://chrome.google.com/webstore/detail/cookiestxt/njabckikapfpffapmjgojcnbfjonfjfg), so I propose to change the link in the README.md to another similar extension called Get cookies.txt (https://chrome.google.com/webstore/detail/get-cookiestxt/bgaddhkoddajcdgocldbbfleckgcbcid/) with the same functions and utility of the old one.

This PR close #26885