remote: add camel-cased *.tagOpt key, like clone

Change "git remote add" so that it adds a *.tagOpt key, and not the
lower-cased *.tagopt on "git remote add --no-tags", just as "git clone
--no-tags" would do.

This doesn't matter for anything that reads the config. It's just
prettier if we write config keys in their documented camelCase form to
user-readable config files.

When I added support for "clone -no-tags" in 0dab2468ee (clone: add a
--no-tags option to clone without tags, 2017-04-26) I made it use
the *.tagOpt form, but the older "git remote add" added in
111fb85865 (remote add: add a --[no-]tags option, 2010-04-20) has
been using *.tagopt all this time.

It's easy enough to add a test for this, so let's do that. We can't
use "git config -l" there, because it'll normalize the keys to their
lower-cased form. Let's add the test for "git clone" too for good
measure, not just to the "git remote" codepath we're fixing.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/remote.c

@@ -221,7 +221,7 @@ static int add(int argc, const char **argv)
 
 	if (fetch_tags != TAGS_DEFAULT) {
 		strbuf_reset(&buf);
-		strbuf_addf(&buf, "remote.%s.tagopt", name);
+		strbuf_addf(&buf, "remote.%s.tagOpt", name);
 		git_config_set(buf.buf,
 			       fetch_tags == TAGS_SET ? "--tags" : "--no-tags");
 	}

t/t5505-remote.sh

@@ -591,6 +591,7 @@ test_expect_success 'add --no-tags' '
 		cd add-no-tags &&
 		git init &&
 		git remote add -f --no-tags origin ../one &&
+		grep tagOpt .git/config &&
 		git tag -l some-tag >../test/output &&
 		git tag -l foobar-tag >../test/output &&
 		git config remote.origin.tagopt >>../test/output

t/t5612-clone-refspec.sh

@@ -94,6 +94,7 @@ test_expect_success 'by default no tags will be kept updated' '
 test_expect_success 'clone with --no-tags' '
 	(
 		cd dir_all_no_tags &&
+		grep tagOpt .git/config &&
 		git fetch &&
 		git for-each-ref refs/tags >../actual
 	) &&