Warnings about libraries/wallet/Doxyfile.in

**Build Error Description**

```
#10 3976.7 [ 92%] Generating doxygen/perlmod/DoxyDocs.pm
#10 3976.8 warning: Tag 'PERL_PATH' at line 2054 of file 'Doxyfile' has become obsolete.
#10 3976.8 To avoid this warning please remove this line from your configuration file or upgrade it using "doxygen -u"
#10 3976.8 warning: Tag 'MSCGEN_PATH' at line 2076 of file 'Doxyfile' has become obsolete.
#10 3976.8 To avoid this warning please remove this line from your configuration file or upgrade it using "doxygen -u"
```

**Build Environment**
Details about the build environment, including the relevant required libraries. Much of this information can be found in the `CMakeFiles/CMakeOutput.log`.
- Host OS: Docker
- Host Physical RAM: /
- Source Branch/Tag: `develop`
- OpenSSL Version: /
- Boost Version: /
- C++ Compiler: /

## CORE TEAM TASK LIST
- [ ] Evaluate `Build Error`
- [ ] Provide build guidance
- [ ] Create `Bug Report`

Open libraries/wallet/Doxyfile.in and inspect the PERL_PATH and MSCGEN_PATH entries identified in the build log. Reproduce the Docker build, remove or update the obsolete configuration entries as appropriate, and confirm Doxygen no longer emits these warnings.

Written by the indexing model from the issue text.