[CI]: enable caching for yarn actions

[imLinguin]

Use the following Checklist if you have changed something on the Backend or Frontend:

• Tested the feature and it's working on a current and clean install.
• Tested the main App features and they are still working on a current and clean install. (Login, Install, Play, Uninstall, Move games, etc.)
• Created / Updated Tests (If necessary)
• Created / Updated documentation (If necessary)

[imLinguin]

For some reason yarn on windows has trouble connecting to repo, I guess I can just roll that back, other builds are speed up already

[flavioislima]

LGTM