Enable running integration specs for different setups

[einari]

Today we have the integration specs in Integration/DotNET.InProcess that runs with a MongoDB setup with the Kernel in process.
We want to reuse the specs but just run them for different types of environments and setups. With this we also want to improve the build pipelines for this.

Tasks:

• Create a folder within the Integration folder at the root of the repository calledSpecifications
• Move all the actual specs into this new Specifications folder
• Update DotNET.InProcess project to include all the files as <Compile/> from the Specifications folder
• Add a new project called DotNET and set it up to be not in process by leveraging a container, in the same way we've done it for the Api integration specs.
• Fix the build pipeline (botnet-build.yml - integration-specs) to be dynamic with regards to the namespace matrix, it should use the top level folders from the new Specifications as namespaces.
• Add a second dimension to the matrix with running multiple projects (DotNET.InProcess, DotNET) - we will expand with more later