t6[0-3]*: adjust the references to the default branch name "main"

Carefully excluding t6300, which sees independent development elsewhere
at the time of writing, we use `main` as the default branch name in
t6[0-3]*. This trick was performed via

	$ (cd t &&
	   sed -i -e 's/master/main/g' -e 's/MASTER/MAIN/g' \
		-e 's/Master/Main/g' -- t6[0-3]*.sh &&
	   git checkout HEAD -- t6300\*)

This allows us to define `GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main`
for those tests.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/t6006-rev-list-format.sh b/t/t6006-rev-list-format.sh
index bbbd577..35a2f62 100755
--- a/t/t6006-rev-list-format.sh
+++ b/t/t6006-rev-list-format.sh
@@ -5,7 +5,7 @@
 
 test_description='git rev-list --pretty=format test'
 
-GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=master
+GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
 . ./test-lib.sh
@@ -56,7 +56,7 @@
 test_format () {
 	cat >expect.$1
 	test_expect_${3:-success} "format $1" "
-		git rev-list --pretty=format:'$2' master >output.$1 &&
+		git rev-list --pretty=format:'$2' main >output.$1 &&
 		test_cmp expect.$1 output.$1
 	"
 }
@@ -187,13 +187,13 @@
 	<RED>foo<GREEN>bar<BLUE>baz<RESET>xyzzy
 	EOF
 	format="%Credfoo%Cgreenbar%Cbluebaz%Cresetxyzzy" &&
-	git rev-list --color --format="$format" -1 master >actual.raw &&
+	git rev-list --color --format="$format" -1 main >actual.raw &&
 	test_decode_color <actual.raw >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success '%S is not a placeholder for rev-list yet' '
-	git rev-list --format="%S" -1 master | grep "%S"
+	git rev-list --format="%S" -1 main | grep "%S"
 '
 
 test_expect_success 'advanced colors' '
@@ -202,7 +202,7 @@
 	<BOLD;RED;BYELLOW>foo<RESET>
 	EOF
 	format="%C(red yellow bold)foo%C(reset)" &&
-	git rev-list --color --format="$format" -1 master >actual.raw &&
+	git rev-list --color --format="$format" -1 main >actual.raw &&
 	test_decode_color <actual.raw >actual &&
 	test_cmp expect actual
 '
@@ -409,7 +409,7 @@
 
 test_expect_success '%ad respects --date=' '
 	echo 2005-04-07 >expect.ad-short &&
-	git log -1 --date=short --pretty=tformat:%ad >output.ad-short master &&
+	git log -1 --date=short --pretty=tformat:%ad >output.ad-short main &&
 	test_cmp expect.ad-short output.ad-short
 '
 
@@ -497,8 +497,8 @@
 '
 
 test_expect_success '%gd shortens ref name' '
-	echo "master@{0}" >expect.gd-short &&
-	git log -g -1 --format=%gd refs/heads/master >actual.gd-short &&
+	echo "main@{0}" >expect.gd-short &&
+	git log -g -1 --format=%gd refs/heads/main >actual.gd-short &&
 	test_cmp expect.gd-short actual.gd-short
 '