[CECO-1860][DatadogGenericResource] Add monitor support

[tbavelier]

What does this PR do?

• Adds support for monitor as a DatadogGenericResource

Motivation

• Supporting all monitors covered by the API, e.g.:

  apiVersion: datadoghq.com/v1alpha1
  kind: DatadogGenericResource
  metadata:
    name: monitor
  spec:
      type: monitor
      jsonSpec: |-
        {
          "name": "Example Monitor",
          "type": "composite",
          "query": "60693519 && 135415923",
          "message": "some message Notify: @hipchat-channel",
          "tags": [
            "test:examplemonitor",
            "env:ci"
          ],
          "priority": 3
        }

Additional Notes

This is based on refactor introduced in #1634

Minimum Agent Versions

Are there minimum versions of the Datadog Agent and/or Cluster Agent required?

• Agent: vX.Y.Z
• Cluster Agent: vX.Y.Z

Describe your test plan

Same as #1534 but using the object in Motivation: test the whole lifecycle of the object: create, update, (optionally: update from UI (waiting for the forcesync)), delete

Checklist

• PR has at least one valid label: bug, enhancement, refactoring, documentation, tooling, and/or dependencies
• PR has a milestone or the qa/skip-qa label

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 77 lines in your changes missing coverage. Please review.

Project coverage is 48.79%. Comparing base (049c0b0) to head (ace4a7a).

Files with missing lines	Patch %	Lines
...rnal/controller/datadoggenericresource/monitors.go	0.00%	63 Missing ⚠️
pkg/datadogclient/client.go	0.00%	7 Missing ⚠️
...al/controller/datadoggenericresource/controller.go	0.00%	5 Missing ⚠️
...nternal/controller/datadoggenericresource/utils.go	0.00%	2 Missing ⚠️

Additional details and impacted files

@@                               Coverage Diff                                @@
##           tbavelier/levan-m/generic-resoource-refactor    #1635      +/-   ##
================================================================================
- Coverage                                         48.96%   48.79%   -0.17%     
================================================================================
  Files                                               217      218       +1     
  Lines                                             20880    20950      +70     
================================================================================
  Hits                                              10223    10223              
- Misses                                            10117    10187      +70     
  Partials                                            540      540              

Flag	Coverage Δ
unittests	48.79% <0.00%> (-0.17%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...nternal/controller/datadoggenericresource/utils.go	89.83% <0.00%> (-3.16%)	⬇️
...al/controller/datadoggenericresource/controller.go	39.25% <0.00%> (+0.28%)	⬆️
pkg/datadogclient/client.go	0.00% <0.00%> (ø)
...rnal/controller/datadoggenericresource/monitors.go	0.00% <0.00%> (ø)

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 049c0b0...ace4a7a. Read the comment docs.