emitKeyPathSubscriptOperands() uses the ArgEmitter to collect
index arguments, which uses ResilienceExpansion::Minimal when
lowering parameter types.
For this reason, lowerKeyPathSubscriptIndexTypes() should also
use ResilienceExpansion::Minimal when lowering parameter types.
Otherwise, we crash in the SIL verifier due to a loadable vs
address-only mismatch, if the index type is resilient.
Fixes rdar://problem/144654366.
Fixes https://github.com/swiftlang/swift/issues/79304.
