Build: make a smaller tgz for opam

3 jobs for 2.70.6 in 3 minutes and 38 seconds
latest
Status Job ID Name Coverage
  Build
passed #93639
build

00:02:02

 
  Test
passed #93641
allowed to fail
test_opam_test

00:01:35

failed #93640
allowed to fail
test_opam_test

00:01:18