Client Certificate Authentication in WebCmdlets Unavailable for macOS #4650

Due to an upstream incompatibility between CoreFX and macOS's implementation of curl (dotnet/corefx#19718), the addition of Client Certificate Authentication in PowerShell 6 (#4546) presents the user with an error on macOS when attempting to use -Certificate with Invoke-Webrequest and Invoke-RestMethod

Steps to reproduce

$certficiate = Get-PFXCertificate -Path c:\path\to\cert.pfx
$Result = Invoke-WebRequest -uri https://localhost:8083 -Certificate $certificate
$Result.StatusCode

Expected behavior

200

Actual behavior

An error message containing the following:

The handler does not support client authentication certificates with this combination of libcurl (7.55.1)

Environment data

Name                           Value
----                           -----
PSVersion                      6.0.0-beta
PSEdition                      Core
GitCommitId                    v6.0.0-beta.5-78-gcdbbb7a4bb51929470a5ace096999db155a865b2

on macOS 10.12

References

#3648