chore(build): generates Linux binaries on CentOS 7 MONGOSH-435

[addaleax]

For lowering our glibc requirements:

• We run builds on Centos 7
• We test the executable on a few more platforms, including:
  • RHEL 7.0 and 7.6 (to make sure the lower glibc requirement works)
  • Ubuntu 16.04 (because that was our previous minimum version)
  • Ubuntu 20.04 (because why not, it’s a more modern distro and we should check those as well)