Add imagePullSecrets to Custom Executors

[f-helm]

Is your feature request related to a problem? Please describe. When trying to use a private image registry with a custom executor, it is not possible to pull the image: failed to pull and unpack image "<image-url>:latest": failed to resolve reference "<image-url>:latest": failed to authorize: failed to fetch anonymous token: unexpected status: 403 Forbidden

Describe the solution you'd like Would be great to have a possibility to add (imagepull-)secrets for the private registry so a custom executor can be pulled from there, similar to container executors: https://kubeshop.github.io/testkube/test-types/container-executor/

Describe alternatives you've considered Container executors might be an alternative for some use cases, but do not provide the features a custom executor does.

[TheBrunoLopes]

This could be just a field on the yaml with where the user can put the reference/name of the secret with the private repository credentials. Seems straightforward. do you agree ? @povilasv @vladtobar @exu

[vsukhin]

We already have it in Executor CRD, just need to add support to job template

[povilasv]

We just released a version with this feature, example:

apiVersion: executor.testkube.io/v1
kind: Executor
metadata:
  name: curl-executor
  namespace: testkube
spec:
  image: kubeshop/testkube-curl-executor:1.0.6
  types:
  - curl/test
  imagePullSecrets:
    - name: secret-name

Launches a job with:

apiVersion: batch/v1
kind: Job
metadata:
  name: 6336d432358866734dfda8da
  namespace: testkube
spec:
  selector:
    matchLabels:
      controller-uid: 9c04a6f1-ce7c-43cc-9bfe-0e0343812b72
  template:
    spec:
      containers:
      - command:
        - /bin/runner
     ...
.     imagePullSecrets:
      - name: secret-name