os/mac/pkgconfig/14: update libcurl for 14.5 SDK

[Bo98]

macOS 14.5 SDK has been an Xcode-exclusive SDK until now, so we never updated this pc file. CLT 16 will however include macOS 14.5 SDK so we can update this now.

While the 8.6.0 runtime supports NTLM_WB, the 8.6.0 curl-config dropped the reference to it ahead of Apple dropping it in macOS 14.6's curl 8.7.1 update, which never received a corresponding SDK. Not reporting a feature seems like the safest option.

This PR may have to wait until after the CLT is released fully.

[Bo98]

This PR may have to wait until after the CLT is released fully.

CI agrees. If you see the CI here suddenly break in a couple weeks then this is the PR to merge to fix it.

[carlocab]

Seeing

Failures:

  1) pkg-config returns the correct version for libcurl
     Failure/Error: expect(pc_version("libcurl")).to eq(version)

       expected: "8.6.0"
            got: "8.4.0"

       (compared using ==)
     # ./test/os/mac/pkgconfig_spec.rb:53:in `block (2 levels) in <top (required)>'

in CI now.

https://github.com/Homebrew/brew/actions/runs/10958495800/job/30428868352?pr=18364#step:12:118