fix(is-ignored): ignore "amend!" commits (#4024)

* fix(is-ignored): ignore "amend!" commits

* add test

@commitlint/is-ignored/src/defaults.ts

@@ -20,7 +20,7 @@ export const wildcards: Matcher[] = [
 	),
 	test(/^(Merge tag (.*?))(?:\r?\n)*$/m),
 	test(/^(R|r)evert (.*)/),
-	test(/^(fixup|squash)!/),
+	test(/^(amend|fixup|squash)!/),
 	isSemver,
 	test(/^(Merged (.*?)(in|into) (.*)|Merged PR (.*): (.*))/),
 	test(/^Merge remote-tracking branch(\s*)(.*)/),

@commitlint/is-ignored/src/is-ignored.test.ts

@@ -124,6 +124,10 @@ test('should ignore npm semver commits with footers', () => {
 	);
 });
 
+test('should return true amend commits', () => {
+	expect(isIgnored('amend! initial commit')).toBe(true);
+});
+
 test('should return true fixup commits', () => {
 	expect(isIgnored('fixup! initial commit')).toBe(true);
 });