Change Azure Pipelines yaml to separate build of booter and CLR

[josesimoes]

No need to keep building and releasing booter versions when nothing has changed. Currently nanoBooter is always build along with the nanoCLR which is a waste of time and computing resource. Not to mention that is misleading because you actually don't know if there were any changes or not.

[networkfusion]

We no longer use appveyor. Is this still applicable?

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.