Improve on return documentation

Author: vietqhoang

lib/redis/commands/hashes.rb

@@ -263,7 +263,7 @@ def hscan_each(key, **options, &block)
       # @param [String] key
       # @param [Integer] ttl
       # @param [Array<String>] fields
-      # @return [Array<Integer>] The number of fields that were added to the hash
+      # @return [Array<Integer>] Feedback on if the fields have been updated. See https://redis.io/docs/latest/commands/hexpire/ for array reply.
       def hexpire(key, ttl, *fields)
         send_command([:hexpire, key, ttl, 'FIELDS', fields.length, *fields])
       end