Doc/Michelson: adapt syntax for deprecated instructions

Context

As deprecated instructions don't fit well in the interactive reference (see michelson-reference!124 (merged)), they are kept in the static reference. But we adapt their typing rule so that they match that found in the interactive 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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