[Feature Request] Add e2e test

**FEATURE REQUEST**
1. Please describe the feature you are requesting.
Currently, I notice that this repository lacks any end-to-end (e2e) tests. This could lead to instability in the project. I recommend adding e2e tests to the repository to ensure code robustness every time a user submits a pull request (PR). I suggest using the tool "kuttl", which operates via YAML.

2. Provide any additional detail on your proposed use case for this feature.
see https://kuttl.dev/

2. Indicate the importance of this issue to you (blocker, must-have, should-have, nice-to-have). Are you currently using any workarounds to address this issue?
SHOULD-HAVE

4. If there are some sub-tasks using -[] for each subtask and create a corresponding issue to map to the sub task:
- [todo](example_sub_issue1_link_here): sub-task1 description here,
- [todo](example_sub_issue2_link_here): sub-task2 description here,
- ...