Skip unnecessary PdmBasicAuth initialization to accelerate pdm run execution

[jingfelix]

related issue: #3673 #3669

I used viztracer to inspect the execution flow of pdm run and discovered that a lot of time is consumed when importing PdmBasicAuth at src/pdm/environments/base.py:43.

PdmBasicAuth is used to assign a value to self.auth. For most users who do not set any authentication-related parameters, initializing PdmBasicAuth might be unnecessary?

Perhaps we can implement an early check here to avoid importing PdmBasicAuth if authentication is not needed for the client.

    def __init__(self, project: Project, *, python: str | None = None) -> None:
        """
        :param project: the project instance
        """
        # from pdm.models.auth import PdmBasicAuth

        if isinstance(project, weakref.ProxyTypes):
            self.project = project
        else:
            self.project = weakref.proxy(project)
        self.python_requires = project.python_requires
        # self.auth = PdmBasicAuth(project.core.ui, self.project.sources)
        self.auth = None
        if python is None:
            self._interpreter = project.python
        else:
            self._interpreter = PythonInfo.from_path(python)

Attached are the test results:

// with PdmBasicAuth:
> time pdm run ./test.py
hello
pdm run ./test.py  0.33s user 0.04s system 100% cpu 0.373 total

// without PdmBasicAuth:
> time pdm run ./test.py
hello
pdm run ./test.py  0.22s user 0.02s system 99% cpu 0.245 total

[frostming]

We can simply make it a cached_property that will be initialized when needed (by the package finder). Most time it won't be called. Would you like to contribute?