Add tests for `dis` command-line interface

[picnixz]

The dis CLI (added in 3.10 or so) is lacking tests. I'll be writing them tomorrow or tonight, depending on when I'm done with my IRL tasks.

I think we can backport tests for all command-line options that were introduced in previous versions (up to 3.12) and only write tests for those that were introduced in 3.14 (namely --show-positions (#123168) and --specialized (#127414), and maybe more, but those I've added those two so I know they are 3.14+). To that end, I'll write two separate PRs so to ease backports.

cc @iritkatriel

Linked PRs

• gh-127637: add tests for dis command-line interface #127759
• [3.12] gh-127637: add tests for dis command-line interface (#127759) #127780
• [3.13] gh-127637: add tests for dis command-line interface (#127759) #127781

[picnixz]

(Removing the interpreter-core label because it will only affect the Lib/test directory and not others)