Remove getters.js for roadmap

getters.js was accidentally left unremoved (it should have been removed)
in https://gitlab.com/gitlab-org/gitlab/-/merge_requests/50158/

ee/app/assets/javascripts/roadmap/store/getters.js

-import { newDate } from '~/lib/utils/datetime_utility';
-
-import { PRESET_TYPES, DAYS_IN_WEEK } from '../constants';
-
-/**
- * Returns number representing index of last item of timeframe array from state
- *
- * @param {Object} state
- */
-export const lastTimeframeIndex = (state) => state.timeframe.length - 1;
-
-/**
- * Returns first item of the timeframe array from state
- *
- * @param {Object} state
- */
-export const timeframeStartDate = (state) => {
-  if (state.presetType === PRESET_TYPES.QUARTERS) {
-    return state.timeframe[0].range[0];
-  }
-  return state.timeframe[0];
-};
-
-/**
- * Returns last item of the timeframe array from state depending on preset
- * type set.
- *
- * @param {Object} state
- * @param {Object} getters
- */
-export const timeframeEndDate = (state, getters) => {
-  if (state.presetType === PRESET_TYPES.QUARTERS) {
-    return state.timeframe[getters.lastTimeframeIndex].range[2];
-  } else if (state.presetType === PRESET_TYPES.MONTHS) {
-    return state.timeframe[getters.lastTimeframeIndex];
-  }
-  const endDate = newDate(state.timeframe[getters.lastTimeframeIndex]);
-  endDate.setDate(endDate.getDate() + DAYS_IN_WEEK);
-  return endDate;
-};