fix: handle URL encoded paths in AppOverrideFilter

[netroms]

Summary

The AppOverrideFilter was incorrectly handling paths containing URL encoded characters (like spaces encoded as %20) by extracting the "raw" encoded URL with the request.getRequestURI() method. This caused issues with file paths containing spaces, such as font files (e.g. "Open Sans Regular").

The fix simplifies the path handling by using request.getPathInfo() which provides the correct decoded path after the servlet mapping part of the URL. This ensures proper handling of paths containing spaces and other URL encoded characters, while also being more maintainable by using the standard Servlet API as intended.

Manual test:

1. Try to access the URL: http://localhost:8080/dhis-web-maps/fonts/Open Sans Bold/6144-6399.pbf (double check on the file system that this path actually exist in the installed/overridden app folder, the .pdf file names can vary)
2. Make sure you can access it.
3. Install an overridden app version from the "App management" app. We chose to install the map app, since it contains fonts that have spaces in it.
4. Try to access the same URL: http://localhost:8080/dhis-web-maps/fonts/Open Sans Bold/6144-6399.pbf (make sure it actually exists on file system first, the .pbf files can vary from map app version)
5. Make sure you also can access it.

TIP: The file system path for installed apps looks similar to this: DHIS2_HOME_FOLDER/files/apps/maps_101.0.1/fonts/Open Sans Bold

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
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

[david-mackessy]

Was a request like /dhis-web-maps/fonts/Open%20Sans%20Regular/0-255.pbf checked to see if that works also?
Also, I know Spring filters are hard to test in our setup so testing this is very difficult. Without actually looking into how to test this, it seems a shame not to have a test for something that could easily be changed again in the future. Just calling it out.