Without this, verifying TLS certificates would fail on macOS, as well
as any system that doesn't have a certificate file at /etc/ssl/certs/ca-certificates.crt,
which includes e.g. Fedora.
Change-Id: Iaa2e0e9db3747645b5482c82e3e0e4e8f229f5f9
This is better for privacy and to avoid leaking netrc credentials in a
MITM attack, but also the assumption that we check the hash no longer
holds in some cases (in particular for impure derivations).
Partially reverts https://github.com/NixOS/nix/commit/5db358d4d78aea7204a8f22c5bf2a309267ee038.
(cherry picked from commit c04bc17a5a0fdcb725a11ef6541f94730112e7b6)
(cherry picked from commit f2f47fa725fc87bfb536de171a2ea81f2789c9fb)
(cherry picked from commit 7b39cd631e0d3c3d238015c6f450c59bbc9cbc5b)
Upstream-PR: https://github.com/NixOS/nix/pull/11585
Change-Id: Ia973420f6098113da05a594d48394ce1fe41fbb9