Improve Harbor security on workload cluster
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### Summary
Improve Harbor security on workload cluster.
- [ ] Use a random password for admin account
- [ ] Configure TLS with not auto-generated certificates
#### related references
Harbor deployment on workload cluster: https://gitlab.com/sylva-projects/sylva-core/-/issues/858
Cluster secrets: https://gitlab.com/sylva-projects/sylva-core/-/commit/419e131dfdec86b7aee92871c88667f2358fb19b
### Details
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issue