Mention New Feature in release notes

Access to remote HTTPS repositories
that requires client certificates [can be
enabled](git-for-windows/git#3292). This
is now necessary because [cURL no longer sends client certificates by
default](curl/curl@54e7475).

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

ReleaseNotes.md

@@ -47,6 +47,7 @@ This package contains software from a number of other projects including Bash, z
 * The Windows Terminal profile is now identified [by a GUID](https://github.com/git-for-windows/build-extra/pull/356), for more robust customization.
 * Comes with [GNU Privacy Guard v2.2.28](https://lists.gnupg.org/pipermail/gnupg-announce/2021q2/000460.html).
 * Comes with [Git Credential Manager Core v2.0.475.64295](https://github.com/microsoft/git-credential-manager-core/releases/tag/v2.0.475).
+* Access to remote HTTPS repositories that requires client certificates [can be enabled](https://github.com/git-for-windows/git/issues/3292). This is now necessary because [cURL no longer sends client certificates by default](https://github.com/curl/curl/commit/54e747501626b81149b1b44949119d365db82004).
 
 ### Bug Fixes