Add project releases evidences to Import/Export & GitLab Migration

Related to #339422 (closed)

Release Notes

We continue to add support for more metadata to GitLab migration. In GitLab 15.1, we’ve added releases evidences to Import/Export & GitLab Migration. This metadata will help you migrate more of the data without needing to manually copy over releases evidences.

Project Import/Export & GitLab Migration importers migrate project releases. However, they do not contain evidence information.

We should include this information whem migrating projects.

Proposed solution

1. MR 1 - add evidences to import_export.yml (similar to releases milestone MR !85598 (merged))
2. Add ReleaseEvidencesPipeline to GitLab Migration (similar to !85608 (merged))

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