Remove validation webhook for LogPipelines

[a-thaler]

Description
Out of the experiences gathered, an advanced validation of a pipeline should not be done in a webhook as it takes time, might not be available and anyway need to get repeated at server side again.
Syntactical checks can be done nicely in the CRD definition already.

So the gola is to move all parts of the current webhook to an adequate replacement and get rid of the webhook

Criterias

• The webhook is removed
• All validation got replaced by adequate replacements

Tasks
- [ ] Move unsupported mode warning
- [ ] Max Pipeline check to be executed on backend side similar to TracePipeline, having proper status change
- [ ] Singleton check for telemetry resource #555
- [ ] Plugin validation with supported list and hardcoded available plugin list as backend validation feature reflected via status change
- [ ] Missing file/variable reference validation
- [x] Delete dry-run and get manager image free (#1234)
- [ ] Move API validation into CRD schema validation
- [ ] Delete webhook

Reasons

Attachments

Release Notes

[github-actions]

This issue has been automatically marked as stale due to the lack of recent activity. It will soon be closed if no further activity occurs.
Thank you for your contributions.

[a-thaler]

We decided to stay with the validating webhook. The heavy operation of performing dry-runs was removed. We anyway will not get rid of webhooks and the cert mechanism seem to work reliable. So instead we will focus on shifting to OTEL and remove the webhook once we remove fluentbit