feat: move upgrade script and make it shorter

src/upgrades/1.16.0/category_tags.js

@@ -10,17 +10,6 @@ module.exports = {
 	timestamp: Date.UTC(2020, 10, 23),
 	method: async function () {
 		const progress = this.progress;
-		const cache = {};
-		async function categoryTagCount(cid, tag) {
-			if (cache[cid] && cache[cid][tag]) {
-				return cache[cid][tag];
-			}
-			const count = await db.sortedSetIntersectCard(
-				['cid:' + cid + ':tids:lastposttime', 'tag:' + tag + ':topics']
-			);
-			cache[cid] = cache[cid] || {};
-			cache[cid][tag] = count;
-		}
 
 		await batch.processSortedSet('topics:tid', async function (tids) {
 			await async.eachSeries(tids, async function (tid) {
@@ -32,11 +21,9 @@ module.exports = {
 				if (tags.length) {
 					const cid = topicData.cid;
 					await async.eachSeries(tags, async function (tag) {
-						const count = await categoryTagCount(cid, tag);
-						if (count > 0) {
-							await db.sortedSetAdd('cid:' + cid + ':tags', count, tag);
 						await db.sortedSetAdd('cid:' + cid + ':tag:' + tag + ':topics', topicData.timestamp, tid);
-						}
+						const count = await db.sortedSetCard('cid:' + cid + ':tag:' + tag + ':topics');
+						await db.sortedSetAdd('cid:' + cid + ':tags', count, tag);
 					});
 				}