Support new expire features (#2036)

* Support new expire features

* Update PEXPIRETIME.ts

* Update EXPIRETIME.ts

* fix version skip

* clean code

Co-authored-by: leibale <leibale1998@gmail.com>

packages/client/lib/commands/EXPIRETIME.spec.ts

@@ -0,0 +1,21 @@
+import { strict as assert } from 'assert';
+import testUtils, { GLOBAL } from '../test-utils';
+import { transformArguments } from './EXPIRETIME';
+
+describe('EXPIRETIME', () => {
+    testUtils.isVersionGreaterThanHook([7, 0]);
+    
+    it('transformArguments', () => {
+        assert.deepEqual(
+            transformArguments('key'),
+            ['EXPIRETIME', 'key']
+        );
+    });
+
+    testUtils.testWithClient('client.expireTime', async client => {
+        assert.equal(
+            await client.expireTime('key'),
+            -2
+        );
+    }, GLOBAL.SERVERS.OPEN);
+});