Trying to fix CI (issue with selenium-webdrivers)

[pablobm]

For some reason, we can't get v4.9.1 from CircleCI:

Fetching gem metadata from https://rubygems.org/..........
Resolving dependencies...
Your bundle is locked to selenium-webdriver (4.9.1) from rubygems repository
https://rubygems.org/ or installed locally, but that version can no longer be
found in that source. That means the author of selenium-webdriver (4.9.1) has
removed it. You'll need to update your bundle to a version other than
selenium-webdriver (4.9.1) that hasn't been removed in order to install.

Exited with code exit status 7

CircleCI received exit code 7