Merge branch 'js/objects-larger-than-4gb-on-windows'

Merge branch 'js/objects-larger-than-4gb-on-windows'

Update code paths that assumed "unsigned long" was long enough for
"size_t".

* js/objects-larger-than-4gb-on-windows:
  ci: run expensive tests on push builds to integration branches
  t5608: mark >4GB tests as EXPENSIVE
  test-tool synthesize: add precomputed SHA-256 pack for 4 GiB + 1
  test-tool synthesize: precompute pack for 4 GiB + 1
  test-tool synthesize: use the unsafe hash for speed
  t5608: add regression test for >4GB object clone
  test-tool: add a helper to synthesize large packfiles
  delta, packfile: use size_t for delta header sizes
  odb, packfile: use size_t for streaming object sizes
  git-zlib: handle data streams larger than 4GB
  index-pack, unpack-objects: use size_t for object size