manylinux build

[jraymakers]

• Use manylinux container in Linux builds to avoid binding against newer versions of GLIBCXX, which can fail in environments with older standard libraries (e.g. AWS Lambdas, including Vercel).
• Use the actual Linux ARM runner (now that it's available) for the Linux ARM build, instead of using cross-compilation.
  • This means we can run tests in this job.
• Fix the images of the other builds, so upgrades can be done explicitly, avoiding surprises.