Let requests handle url encoding

[nicogodet]

Previously, if a plugin url was like "https://mypluginrepo.example.com/download.php?plugin=MyPlugin", it raises an error as "?" and "=" where encoded
Trace: 404 Client Error: Not Found for url: https://mypluginrepo.example.com/download.php%3Fplugin%3DMyPlugin
The issue is that quote() would encode the entire URL including the protocol and special characters that should remain unencoded (like ://?=). This would break the URL structure.

download_remote_file_to_local use requests. Let it handle the encoding part and provide instead the base url and query params.

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Guts]

Not sure if it does not break or not any URL but it sounds good to let Requests doing its magic.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

@@            Coverage Diff             @@
##             main     #610      +/-   ##
==========================================
- Coverage   70.63%   70.04%   -0.59%     
==========================================
  Files          47       47              
  Lines        3204     3208       +4     
  Branches      566      566              
==========================================
- Hits         2263     2247      -16     
- Misses        740      755      +15     
- Partials      201      206       +5     

Flag	Coverage Δ
unittests	69.48% <100.00%> (-0.59%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
qgis_deployment_toolbelt/plugins/plugin.py	78.41% <100.00%> (ø)
qgis_deployment_toolbelt/utils/file_downloader.py	75.38% <100.00%> (+1.61%)	⬆️

... and 2 files with indirect coverage changes