t9902: use a non-deprecated command for testing

t9902 had a list of three random porcelain commands as a sanity check,
one of which was filter-branch.  Since we are recommending people not
use filter-branch, let's update this test to use rebase instead of
filter-branch.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: newren

t/t9902-completion.sh

@@ -28,10 +28,10 @@ complete ()
 #
 # (2) A test makes sure that common subcommands are included in the
 #     completion for "git <TAB>", and a plumbing is excluded.  "add",
-#     "filter-branch" and "ls-files" are listed for this.
+#     "rebase" and "ls-files" are listed for this.
 
-GIT_TESTING_ALL_COMMAND_LIST='add checkout check-attr filter-branch ls-files'
-GIT_TESTING_PORCELAIN_COMMAND_LIST='add checkout filter-branch'
+GIT_TESTING_ALL_COMMAND_LIST='add checkout check-attr rebase ls-files'
+GIT_TESTING_PORCELAIN_COMMAND_LIST='add checkout rebase'
 
 . "$GIT_BUILD_DIR/contrib/completion/git-completion.bash"
 
@@ -1392,12 +1392,12 @@ test_expect_success 'basic' '
 	# built-in
 	grep -q "^add \$" out &&
 	# script
-	grep -q "^filter-branch \$" out &&
+	grep -q "^rebase \$" out &&
 	# plumbing
 	! grep -q "^ls-files \$" out &&
 
-	run_completion "git f" &&
-	! grep -q -v "^f" out
+	run_completion "git r" &&
+	! grep -q -v "^r" out
 '
 
 test_expect_success 'double dash "git" itself' '