Mention Bug Fix in release notes

Git GUI [now handles hooks
correctly](git-for-windows/git#1755) in
worktrees other than the main one.

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

Author: dscho

ReleaseNotes.md

@@ -44,6 +44,7 @@ This package contains software from a number of other projects including Bash, z
 
 * The `http.schannel.checkRevoke` setting (which never worked) [was renamed to `http.schannelCheckRevoke`](https://github.com/git-for-windows/git/pull/1747). In the same run, `http.schannel.useSSLCAInfo` (which also did not work, for the same reason) was renamed to `http.schannelUseSSLCAInfo`.
 * [Avoids](https://github.com/git-for-windows/msys2-runtime/commit/f02cd2463d2c7e03fe97b8a1ce35ecffd0714f7e) a stack overflow with recent Windows Insider versions.
+* Git GUI [now handles hooks correctly](https://github.com/git-for-windows/git/issues/1755) in worktrees other than the main one.
 
 ## Changes since Git for Windows v2.17.1(2) (May 29th 2018)