OC/CI/configuration/request/{{ID}}/{{approved}} should use alerts for alert-like information

[ocket8888]

This Bug Report affects these Traffic Control components:

• Traffic Ops

Current behavior:

The response from a PUT request to OC/CI/configuration/request/{{ID}}/{{approved}} is:

{ "response": "Successfully updated configuration." }

(or similar for denials)

Expected behavior:

According to our API guidelines on response bodies:

The response property of a serialized response object MUST only contain object representations as requested by the client. In particular, it MUST NOT contain admonitions, success messages, informative messages, or statistic summaries beyond the scope requested by the client.

So what is currently the response should be a success-level Alert

Steps to reproduce:

Read the docs/make the request