Remove unused code

src/client/app/common/scripts/get-median.ts

-/**
- * 中央値を求めます
- * @param samples サンプル
- */
-export default function(samples) {
-	if (!samples.length) return 0;
-	const numbers = samples.slice(0).sort((a, b) => a - b);
-	const middle = Math.floor(numbers.length / 2);
-	const isEven = numbers.length % 2 === 0;
-	return isEven ? (numbers[middle] + numbers[middle - 1]) / 2 : numbers[middle];
-}