Review RISC-V build times in different environments

[sxa]

We previously had some issues building locally in RISC-V containers on real hardware (Slack thread) which were due to a build-up of defunct processes which has now been resolved with the merging of adoptium/ci-jenkins-pipelines#1067

This issue is to look at the feasibility of moving to using native RISC-V machines now that we have some hosted at Scaleway instead of the qemu-emulated build containers that we are currently using. Noting that moving to native machines would allow us to use --enable-sbom-strace on the RISC-V builds (Ref: adoptium/ci-jenkins-pipelines#1065)

Job/System	Parallelism	build stage time	build time
#43 SpacemiT-K1	-with-jobs=6	2h53	2h21
#45 Azure U22.04	16 (Default)	1h58	1h35
#47 Scaleway TH1520	4	2h45	2h22
#49 SpacemiT-K1	3	4h08	3h35
#27 Ampere U22.04	--with-jobs=80	2h45	2h04
#28 Ampere U22.04	--with-jobs=120	2h42	2h10
#50 Ampere U22.04	160