Bug#1033175: FTBFS: setup.py install is deprecated

[David W. Kennedy]

Package: 0ad
Version: 0.0.26-3
Severity: serious
Tags: ftbfs
Justification: fails to build from source (but built successfully in the 
past)
X-Debbugs-Cc: dave_k at reasoned.us

Hello,

When I try to build 0ad version 0.0.26-3 in Debian unstable with 
python3.11 and python3-virtualenv, build fails.

I think that the key error message is 
"/usr/lib/python3/dist-packages/setuptools/command/install.py:34: 
SetuptoolsDeprecationWarning: setup.py install is deprecated. Use build 
and pip and other standards-based tools."

The commands that I use to build the package:

# apt-get update
# apt-get build-dep 0ad
$ apt-get source 0ad
$ cd 0ad-0.0.26
$ debuild

Here is an excerpt of the output.

[...]

patching file python/mozbuild/mozbuild/preprocessor.py
patching file python/mozbuild/mozbuild/util.py
Creating Python 3 environment
/usr/lib/python3/dist-packages/setuptools/command/install.py:34: 
SetuptoolsDeprecationWarning: setup.py install is deprecated. Use build 
and pip and other standards-based tools.
   warnings.warn(
created virtual environment CPython3.11.2.final.0-64 in 139ms
   creator 
CPython3Posix(dest=/home/myusername/0ad-0.0.26/libraries/source/spidermonkey/mozjs-78.6.0/build-debug/_virtualenvs/init_py3, 
clear=False, global=False)
   seeder FromAppData(download=False, pip=bundle, setuptools=bundle, 
wheel=bundle, via=copy, 
app_data_dir=/home/myusername/.local/share/virtualenv)
     added seed packages: pip==20.2.2, setuptools==49.6.0, wheel==0.35.1
   activators 
BashActivator,CShellActivator,FishActivator,PowerShellActivator,PythonActivator,XonshActivator
Traceback (most recent call last):
   File 
"/home/myusername/0ad-0.0.26/libraries/source/spidermonkey/mozjs-78.6.0/build-debug/../js/src/../../configure.py", 
line 181, in <module>
     sys.exit(main(sys.argv))
              ^^^^^^^^^^^^^^
   File 
"/home/myusername/0ad-0.0.26/libraries/source/spidermonkey/mozjs-78.6.0/build-debug/../js/src/../../configure.py", 
line 52, in main
     sandbox.run(os.path.join(os.path.dirname(__file__), 
'moz.configure'))

[...]