Add IronicNeutronAgentReportInterval with a default of
30 seconds.
Previously the ironic-neutron-agent used the global report
interval in neutron. The global interval was increased to
300s in change: Ib3f7cd9d6c050140a5e8b59adf7fd8f65b12df2f.
While the 300s interval may make sense for other agents,
the ironic-neutron-agent can keep reporting at 30s, the
previous default.
Closes-Bug: #1940838
Depends-On: I6fc0eb085c09fb1e24ff09d4f8199d2cf57dd209
Change-Id: Id77662e9dd466ec8609354c2dbeee8592f599e72
9574cd4d0f