[RNMobile] Add drag & drop help guide in Help & Support screen#4857

fluiddot merged 9 commits intotrunkwordpress-mobile/gutenberg-mobile:trunkfrom

version-toolkit/gutenberg/rnmobile/add/drag-and-drop-help-guidewordpress-mobile/gutenberg-mobile:version-toolkit/gutenberg/rnmobile/add/drag-and-drop-help-guideCopy head branch name to clipboard