fix: dev: Fix strict weak ordering violation in resign_sooner()

resign_sooner_values() only checked whether rhs was SOA-typed when
resign times were equal, but did not check lhs. When both entries were
SOA-typed with equal resign times, the comparison returned true in both
directions, violating irreflexivity and corrupting heap invariants.

Add lhs_typepair parameter and require lhs to be non-SOA for the
tie-breaking logic to apply.

Closes #5884

Merge branch '5884-heap-condition-fix' into 'main'

See merge request isc-projects/bind9!11874