Doc/Michelson: redirect set operations to interactive reference

Context

Answers this part of #4077:

• delete the parts about instructions from the static reference:
  • Operations on sets

The documentation about all the operations on set in the interactive reference contains that found in the static reference. The semantics rule for ITER in the non-empty case differs a bit; I like the version from the interactive reference better, but that's just a matter of taste I think.
The inclusion was checked manually by comparing the static and interactive documentations for each type and comparison instruction of the static reference.

Manually testing the MR

make -C docs -j

And then open docs/_build/alpha/michelson.html in a web browser.

Or open the exposed artifacts Documentation - excluding old protocols below, and navigate to docs/_build/alpha/michelson.html.

Checklist

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