[bazel] Add a way for execution environments to provide their hashfile

### Description

See #26243.

It would be good to have a way that a test could be defined, and via some mechanism we could get the right hashfile of the ROM for each execution environment. The current approach requires hardcoding this for tests that use it like `kmac_app_rom_test`, which is fragile and prone to more errors as we add execution environments or tops.

This might require some Bazel hacking to implement, or could be part of the upcoming build system revamp for multitop.

Start by reading #26243 and the current hashfile handling in kmac_app_rom_test. Investigate the Bazel test definition and the planned multitop build-system revamp to determine how execution environments could provide ROM hashfiles. Done means tests obtain the correct per-environment hashfile without hardcoding it.

Written by the indexing model from the issue text.