Integration test: Force rotation nested spire with self-signed authority

[MarcosDY]

Possible test plan:

Start Nested SPIRE using Self-Signed Authorities

                         root-server
                              |
                         root-agent
                        /           \
         intermediateA-server   intermediateA-server
                |                       |
         intermediateA-agent    intermediateA-agent
                |                       |
           leafA-server            leafA-server
                |                       |
           leafA-agent             leafA-agent

Test steps:

• Create one or more entries per agent.
• Prepare a new bundle in the root-server.
• Verify that the new bundle is propagated to leaf servers/agents.
• Activate the new bundle in the root-server.
• Create a new entry and verify that the SVID is using the new bundle.
• Taint the old authority.
• Verify that all Workload SVIDs from root-agent to leaf agents are updated with new SVIDs.
• Verify that Server and Agent SVIDs are tainted and updated.
• Verify that a workload (X) receives a notification for a new SVID.
• Revoke the old authority.
• Verify that workloads remain connected.