Technique composability

[purva-thakre]

Add a page in the docs about how to alter a Problem Setup when a user wants to stack multiple techniques.

Currently, we can use executors that are compatible with each other (REM+ZNE tutorial) or decorators that are compatible with each other (code blocks from the Mitiq paper in the description of #2280).

• intro
• a section for what makes 2 executors compatible
• examples

[jordandsullivan]

I can plan to contribute on the examples section of this issue with a DDD + ZNE tutorial.

[purva-thakre]

Discussed during the Community Call today to create a table for the performance of stacking techniques in the presence of different noise models.

@jordandsullivan Should we start to add the table as a resource in the docs or start with recording the information in a Google doc as Nathan suggested?