Configuration file ignored

[martinrotter]

1. Create configuration file aqt/settings.ini.
2. Run arbitrary aqt commands.

Configuration file was created deliberately with unreachable "baseurl" to test the behavior.

• When launched without -c switch, then the settings file is apparently not used because aqt uses some internal working Qt mirror.
• When launched with -c switch, then downloading of Qt archives fails as expected.

Sample config:

[aqt]
concurrency: 8
baseurl: https://notfoundbro

[mirrors]
trusted_mirrors:
    https://download.qt.io
blacklist:

fallbacks:

[miurahr]

pls use report template.

[miurahr]

duplicated with #731