Move `iter_swap.pass.cpp` into a new subdirectory: `iterator.cust.swap` for symmetry with the neighboring subdirectory `iterator.cust.move`. Differential Revision: https://reviews.llvm.org/D116992
Move `iter_swap.pass.cpp` into a new subdirectory: `iterator.cust.swap` for symmetry with the neighboring subdirectory `iterator.cust.move`. Differential Revision: https://reviews.llvm.org/D116992