ci: Update to ROCm 6 HIP on Fedora 41

The problem that motivated commit 3a44b8dfc0 (ci: Move job for HIP tests
on Fedora 39 to a dedicated base image, 2024-04-24, v3.30.0-rc1~202^2~11)
turns out to be exposed by spaces in the path to HIP binaries.  Move the
CI work directory to a path without spaces.

Closes: #25932
8 files changed