Fix overoptimized builds: libjs, kiesel, quanta

Targeting native arch on GitHub runners produces
binaries that crash with SIGILL on my hardware.
Target generic ARMv8 and AVX2 CPUs instead.

Fix build

Fixes

jscript: use ~/.cache/jsz-jscript dir, fix stdbuf warning

Fix/improve hub.Dockerfile

Simple 'git pull' should be enough to update repo inside the container.

Bump revisions

Misc fixes, bump revs

hub fix

Tidy up hub image

New benchmark runner script