[Windows] Fix creation of log file

[Nocccer]

• Replaced not allowed characters ( ':' ) with allowed onces ( '_' ) for file creation on windows.
• Can someone with windows test it ?

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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]

It seems it's working

[flavioislima]

Looks Good!