update-from-upstream: Avoid running out of memory while packing
On repositories with a mix of small and big files packing objects while pushing can run out of memory. Set a limit on the memory usage to avoid this.
Original errors:
- https://gitlab.apertis.org/pkg/sdk/firefox-esr/-/jobs/473652
- https://gitlab.apertis.org/pkg/development/rustc/-/jobs/473651
Test pipeline:
Edited by Emanuele Aina