[bin][installdumux] avoid using distutils

What this MR does / why does DuMux need it:

Removes usage of distutils package in the dumux install script, as we now get a warning because the package is deprecated (see here)

• does the new code follow the style guide?
• do the test pipelines pass? (scheduled to merge if succeeds)
• is the code you changed and/or the new code you wrote covered in the test suite? (if not, extend the existing tests or write new ones)
• all files have to end with a \n character. Make sure there is no \ No newline at end of file comment in "Changes" of this MR.

Fixes #1166 (closed)