t7810-grep: bring log --grep tests in common form

The log --grep tests generate the expected out in different ways.
Make them all use command blocks so that subshells are avoided and the
expected output is easier to grasp visually.
Signed-off-by: NMichael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

t/t7810-grep.sh

@@ -435,31 +435,41 @@ test_expect_success 'log grep setup' '
 
 test_expect_success 'log grep (1)' '
 	git log --author=author --pretty=tformat:%s >actual &&
-	( echo third ; echo initial ) >expect &&
+	{
+		echo third && echo initial
+	} >expect &&
 	test_cmp expect actual
 '
 
 test_expect_success 'log grep (2)' '
 	git log --author=" * " -F --pretty=tformat:%s >actual &&
-	( echo second ) >expect &&
+	{
+		echo second
+	} >expect &&
 	test_cmp expect actual
 '
 
 test_expect_success 'log grep (3)' '
 	git log --author="^A U" --pretty=tformat:%s >actual &&
-	( echo third ; echo initial ) >expect &&
+	{
+		echo third && echo initial
+	} >expect &&
 	test_cmp expect actual
 '
 
 test_expect_success 'log grep (4)' '
 	git log --author="frotz\.com>$" --pretty=tformat:%s >actual &&
-	( echo second ) >expect &&
+	{
+		echo second
+	} >expect &&
 	test_cmp expect actual
 '
 
 test_expect_success 'log grep (5)' '
 	git log --author=Thor -F --pretty=tformat:%s >actual &&
-	( echo third ; echo initial ) >expect &&
+	{
+		echo third && echo initial
+	} >expect &&
 	test_cmp expect actual
 '
 
@@ -473,7 +483,9 @@ test_expect_success 'log --grep --author implicitly uses all-match' '
 	# grep matches initial and second but not third
 	# author matches only initial and third
 	git log --author="A U Thor" --grep=s --grep=l --format=%s >actual &&
-	echo initial >expect &&
+	{
+		echo initial
+	} >expect &&
 	test_cmp expect actual
 '