Migrate image syncer to Github actions

[Sawthis]

Description

Migrate below Prow jobs to Github actions and delete them.

• pre-main-test-infra-image-syncer-dry-run
  - Dry-run of sync images from external sources to Kyma owned registry, is this still our responsibility, is this repo with external images still needed?
• post-main-test-infra-image-syncer-run
  • sync images from external sources to Kyma owned registry, is this still our responsibility, is this repo with external images still needed?

Reasons

Acceptance Criteria

• All Prow jobs mentioned in this issue are migrated to Github actions.
• All Prow jobs mentioned in this issue are removed.

Attachments

#9470

[github-actions]

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Thank you for your contributions.

[github-actions]

This issue has been automatically closed due to the lack of recent activity.
/lifecycle rotten