Fix/5547

[drew2a]

This PR partially fixes #5547 by:

1. Changing default API port number from 8085 to 52194
2. Setting up an organization for QSettings. It should decrease an overlap with other QT applications
3. Adding a get_first_free_port function to ensure that we use a free port for core-gui interaction

There is another probable root case for #5547.
If the previous attempt to run Tribler's did not kill the core process properly, then it can cause the given issue (ref @xoriole)
This particular situation will be addressed in the next PR.

[qstokkink]

Heads-up while this is still in WIP: we already have tribler_core/utilities/network_utils.py to claim free ports. Reusing that in the GUI would require moving it to tribler-common, but it would avoid duplication.

[xoriole]

Seems good to me. There might still be some references to 8085. Can you check and confirm swagger documentation is consistent?

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!

0 Bugs
0 Vulnerabilities
1 Security Hotspot
0 Code Smells

No Coverage information
0.3% Duplication

[drew2a]

@xoriole thank you for noticing this. All related references have been updated.