Enable hotspot/tier1 for 32-bit builds in GHA for 8u

All issues in hotspot/tier1 affecting 32-bit builds are now resolved so these configurations can now be enabled in GHA. This is the last piece to have full tier1 testing on all platforms we have in GHA.

Notes:
- hotspot/tier1 on linux requires working C/C++ compiler for some tests (gcc multilib packages are required for linux-x86)
- hotspot/tier1 contains some container tests, but ubuntu:latest does not include 32-bit libs by default. Multilib image needs to be created.