Clean-up: clang-tidy: unhandled exceptions in noexcept functions

Clean-up: clang-tidy: unhandled exceptions in noexcept functions

While unlikely (would require a corrupted hash table), the iteration adapter's
iterator can theoritically throw an exception during the iteration.

clang-tidy warns that this is bug prone (bugprone-exception-escape).

Change-Id: I89cae7ef662ba6b88c2826a5c8636e0a63fe9117
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>