disable privacy tests since they are currently flaky

[macfarla]

These tests are flaky right now for 2 reasons, and work is in progress to fix.

See

Run tessera as a process (currently using docker) for ATs #5968

Also occasionally errors since the txpool is disabled during initial sync - it's been somewhat mitigated but hasn't totally fixed it

[github-actions]

• I thought about documentation and added the doc-change-required label to this PR if updates are required.
• I thought about the changelog and included a changelog update if required.
• If my PR includes database changes (e.g. KeyValueSegmentIdentifier) I have thought about compatibility and performed forwards and backwards compatibility tests
• I thought about running CI.
• If I did not run CI, I ran as much locally as possible before pushing.

[siladu]

LGTM