test(baremetal): select the best offer for servers based on filters

[elwinar]

This avoids the issue of stocks and hardcoded IDs.

closes #6306

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Relates OR Closes #0000

[github-code-quality]

Code Coverage Overview

Languages: Go

Go / cli

The overall line coverage in commit 854f1d9 in the 6306-baremetal-tests branch remains at 49%, unchanged from commit 374654a in the main branch.

Show a line coverage summary of the most impacted files.

File	main 374654a	6306-baremetal-tests 854f1d9	+/-
core/testing.go	60%	60%	0%
internal/namesp...ustom_server.go	52%	55%	+3%