Building without Seismic Store

Fix a problem where building without Seismic Store still tried to run the SdGlue unit tests. Which would then fail the build.

Add Azure pipelines for building OpenZGY without Seismic Store for all 7 supported Linux distros. Lack of these configurations is the reason why the problem wasn't spotted earlier.

Those configurations are for building inside Schlumberger. Users of the open source are of course free to use those configurations as a starting point, but might have other requirements. Such as not wanting to pay Azure for builds, and/or only needing a single configuration anyway.

There are now 23 build pipelines on-prem in Stavanger. 3 SDAPI flavors (internal, public, and none) times 7 supported distributions. Plus Doxygen and Windows builds.

The gitlab setup still has just one Linux and one Windows build.

Minor note: Running "make docker" or "make LINUXDISTRO=something docker" at the top level has a few caveats compared to what the Azure scripts are doing. So there is still a (very small) residual risk of "make docker" failing when the Azure builds don't.

The Azure jobs won't invoke "make" for building the containers because "make" might not be available. Besides, Azure has different ways of handling parameters so invoking "make" would be inconvenient anyway. Once inside the container, make is run as usual.

Running two "make docker" on the same machine with the same LINUXDISTRO argument will interfere with each other because they will use the same container names. Even if the seismic store type differs.

"make docker" picks up everything in the working directory and pushes it into the container. This includes modified files and files not checked into git (which you probably want) and maybe build outputs (which you don't). Actually the .dockerignore file tries to filter out the latter. But I am paranoid and usually run "make clobber" to remove any binaries in my work area before "make docker".