feat: add gitopsapi delete operation

[Kaitou786]

Description

Exposed a different endpoint starting with /_delete to let the server know that the request is for delete object

Breaking Change

• Yes
• No

Testing Notes

Created a gitopsapi object and sent a post request with a object to the delete endpoint to see it gets deleted
GitOpsApi object used:

apiVersion: git.flanksource.com/v1
kind: GitopsAPI
metadata:
  name: gitopsapi-sample
spec:
  gitRepository: https://github.com/Kaitou786/test-gitops-api.git
  kustomization: clusters/dev01/kustomization.yaml
  secretRef:
    name: git-operator-test
  tokenRef:
    name: token
  branch: random
  searchPath: "clusters/"
  pullRequest:
    body: "my test PR"
    title: "some awesome title"

The post data

{
  "apiVersion": "acmp.corp/v1",
  "kind": "NamespaceRequest",
  "metadata": {
    "name": "tenant3",
    "annotations": {
      "a": "b"
    },
    "labels": {
      "c": "d"
    }
  },
  "spec": {
    "memory": 10,
    "cluster": "dev01"
  },
  "cluster": "dev02"
}

The Curl request:

 curl -X POST 'localhost:8888/_delete/default/gitopsapi-sample/mypassword' -d @data.json

See my testing PR: Kaitou786/test-gitops-api#15
How you can replicate my testing:
How can the reviewer validate this PR?

Links

Issues links or other related resources

[moshloop]

Can we also add an e2e ?

[CLAassistant]

All committers have signed the CLA.

[Kaitou786]

See the diff PRs created by the tests:
flanksource/git-operator-test#343
flanksource/git-operator-test#344
flanksource/git-operator-test#345

[Kaitou786]

Refactored a bit with some more functions. Not sure but let me know about this approach... PRs with this approach:
flanksource/git-operator-test#349
flanksource/git-operator-test#350
flanksource/git-operator-test#351

[Kaitou786]

subset of #46