feat: add object fraq command

Signed-off-by: rfyiamcool <[email protected]>

Author: rfyiamcool

commands_test.go

@@ -675,8 +675,10 @@ var _ = Describe("Commands", func() {
 			Expect(refCount.Err()).NotTo(HaveOccurred())
 			Expect(refCount.Val()).To(Equal(int64(1)))
 
+			client.ConfigSet(ctx, "maxmemory-policy", "volatile-lfu")
 			freq := client.ObjectFreq(ctx, "key")
 			Expect(freq.Err()).NotTo(HaveOccurred())
+			client.ConfigSet(ctx, "maxmemory-policy", "noeviction") // default
 
 			err := client.ObjectEncoding(ctx, "key").Err()
 			Expect(err).NotTo(HaveOccurred())