Address Codewind-Che-Plugin functional test issues on macOS

[johnmcollier]

As part of https://github.com/eclipse/codewind/issues/37, the BATS-based functional tests for the Codewind Che sidecar were delivered. However, we're seeing issues running the tests on macOS, which use a backlevel version of bash, compared to what's available on Linux & WSL.

Seems that when the tests are run on macOS, Codewind is successfully deployed, but the test never detects it and thinks Codewind never came up. This doesn't appear to be seen on other platforms.

We need to make sure that the sidecar functional tests can be easily setup and run on macOS, without having to update the version of bash that's used.

/cc @lentheivendra