commit-graph: add --[no-]progress to write and verify

Add --[no-]progress to git commit-graph write and verify.
The progress feature was introduced in 7b0f229
("commit-graph write: add progress output", 2018-09-17) but
the ability to opt-out was overlooked.

Signed-off-by: Garima Singh <garima.singh@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/t5324-split-commit-graph.sh b/t/t5324-split-commit-graph.sh
index e2c3953..115aabd 100755
--- a/t/t5324-split-commit-graph.sh
+++ b/t/t5324-split-commit-graph.sh
@@ -320,7 +320,7 @@
 	git merge commits/3 commits/4 &&
 	git branch merge/octopus &&
 	git commit-graph write --reachable --split &&
-	git commit-graph verify 2>err &&
+	git commit-graph verify --progress 2>err &&
 	test_line_count = 3 err &&
 	test_i18ngrep ! warning err &&
 	test_line_count = 3 $graphdir/commit-graph-chain