Describe the feature
Admin can activate user registerd by themselves，user-self register api has completed.
d4d6ade

Describe the solution you'd like
https://lists.apache.org/thread.html/r285280835025aaac4d610c5614f89948de2d1938843c4b0bcb3fb7e3%40%3Cdev.dolphinscheduler.apache.org%3E