Split Image Build and E2E Test Workflows

[c-pius]

Description

Image build workflow now supports custom tags: kyma-project/test-infra#11981

This allows us to refactor our pipelines to get rid of the issue wrt. to pull_request_target. Proposal is to have two separate workflows:

1. Triggers the image build and supplies the commit hash as custom tag
   • this workflow MUST continue to use pull_request_target as trigger (security requirement to get a GH token)
2. Waits for the built image with the commit hash as custom tag, once there, starts the rest of the E2E test workflow
   • this workflow MUST use pull_request as trigger (e2e tests and setup should run in the up to date proposed config)

Reasons

Make our E2E tests work properly again

Acceptance Criteria

• Each E2E test run uses an up to date image of the current PR ref
• Each E2E test run executes test code of the current PR ref

Feature Testing

No response

Testing approach

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Attachments

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