src/vs/base/common/strings.ts/ltrim
export function ltrim(haystack: string, needle: string): string {
	if (!haystack || !needle) {
		return haystack;
	}

	const needleLen = needle.length;
	if (needleLen === 0 || haystack.length === 0) {
		return haystack;
	}

	let offset = 0;

	while (haystack.indexOf(needle, offset) === offset) {
		offset = offset + needleLen;
	}
	return haystack.substring(offset);
}