git-revert: add abort example (#15800)

Author: Managor

Diff for: pages/common/git-revert.md

@@ -22,3 +22,7 @@
 - Don't create new commits, just change the working tree:
 
 `git revert {{-n|--no-commit}} {{0c01a9..9a1743}}`
+
+- Cancel a Git revert after a merge conflict:
+
+`git revert --abort`