filter-branch doc: fix filter-repo typo

The name of the tool is 'git-filter-repo' not
'git-repo-filter'.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: chriscool

Documentation/git-filter-branch.txt

@@ -532,7 +532,7 @@ The https://github.com/newren/git-filter-repo/[git filter-repo] tool is
 an alternative to git-filter-branch which does not suffer from these
 performance problems or the safety problems (mentioned below). For those
 with existing tooling which relies upon git-filter-branch, 'git
-repo-filter' also provides
+filter-repo' also provides
 https://github.com/newren/git-filter-repo/blob/master/contrib/filter-repo-demos/filter-lamely[filter-lamely],
 a drop-in git-filter-branch replacement (with a few caveats).  While
 filter-lamely suffers from all the same safety issues as