pip.conf option to disable linehaul metadata in user-agent

[eaubin]

What's the problem this feature will solve?

The user-agent string used by pip includes things such as cpu, os, os version, etc, that my network admins would prefer not be shared.

Describe the solution you'd like

Adding an option to pip.conf to disable linehaul metadata in the user-agent string.

Alternative Solutions

n/a

Additional context

n/a

Code of Conduct

• I agree to follow the PSF Code of Conduct.

[notatallshaw]

I'm not against this (or for it), but FYI, this information leaks regardless, by looking at what wheel and wheel metadata the pip session downloads.