DCManager audit backoff to avoid flooding with RCP messages

[Li Zhu]

Brief Description
-----------------
To avoid flooding with RCP messages during massive outages or any long
lasting failure, the DC audit manager scales back subcloud auditing by
limiting the retry times for the failures in a patch audit cycle
(which is the base of all other types of audit cycles).

Severity
--------
Minor

Steps to Reproduce
------------------
1.Install Distributed Cloud with a bunch of subclouds
2.Trigger a long lasting failure

Expected Behavior
------------------
No RPC message congestion and audit logs will not rotate within a short
amount of time.
The audit performance will not be impacted.

Actual Behavior
----------------
RPC message and audit logs congestion.
The audit performance was somehow impacted.

Reproducibility
---------------
Reproducible

System Configuration
--------------------
Distributed Cloud

Branch/Pull Time/Commit
-----------------------
Starlingx master from 2022-06-21

Last Pass
---------
N/A

Timestamp/Logs
--------------
N/A

Test Activity
-------------
Developer Testing

Workaround
----------
N/A

[OpenStack Infra (hudson-openstack)]

Change abandoned by "Li Zhu <email address hidden>" on branch: master
Review: https://review.opendev.org/c/starlingx/distcloud/+/846626
Reason: redo it later