spanconfigmanager: TestReconciliationJobIsIdle fails to work when pointed at a virtual cluster

[knz]

Describe the problem

After #108762, the test TestReconciliationJobIsIdle fails when pointed to a secondary tenant:

    manager_test.go:268: condition failed to evaluate within 45s: from manager_test.go:270: waiting for reconciliation job to be started

Expected behavior

The test should work with secondary tenants like all other tests in the package.

Epic: CRDB-26687

Jira issue: CRDB-30934

Epic CRDB-26687

[nvb]

spanconfigmanager is owned by SQL foundations, so I'll move this there for tracking.

[arulajmani]

@rimadeodhar this is the test we chatted about in-person which should be on SQL foundations. I'll add the T label.