Build/Test Tools: Update grunt-patch-wordpress for 5.5

Trunk's update happened in [50829]

Seconded by whyisjake and SergeyBiryukov.
Fixes #50829.


Built from https://develop.svn.wordpress.org/branches/5.5@48706


git-svn-id: https://core.svn.wordpress.org/branches/5.5@48468 1a063a9b-81f0-0310-95a4-ce76da25c4cd