Support custom certs and tls auth for private git repositories

[abn]

Similar to how user credentials are handled in #5567 we require git clones to support TLS certificates as available with HTTP repositories.This should also handle in the (presenty in development) verify = false option for repositories.

For this, the get_transport_and_path call will need to pass in the correct vars or use a custom urrlib pool.

poetry/src/poetry/vcs/git/backend.py

Lines 186 to 189 in 1c1cb92

	credentials = get_default_authenticator().get_credentials_for_url(url=url)
	client, path = get_transport_and_path(
	url, username=credentials.username, password=credentials.password
	)

This will also have to be done only for http vcs urls.

Prior to #5428, users could rely on system git client to handle these via options like

git config http.sslverify false

This is no longer possible unless a user forces the system git client backend to be used.

poetry config experimental.system-git-client true

[maayanbar13]

As it seems I'm already on a roll with disabling TLS verification I'll work on this as well :)