Re-enable tab completion of kwargs for large method tables

[mbauman]

while testing to ensure that absurdly large method tables don't tank the performance of the REPL

Fixes #57836

[vtjnash]

You're just essentially demonstrating here that for your specific test case, the subtyping algorithm always takes the fast path--which is true, but seems hardly relevant to the actual point of having this limit

[mbauman]

I don't understand. These tests are effectively for both this change and #54131. Prior to those patches they fail.

I considered using the show MWE from #57836 but it seemed to be bad mojo to effectively test that the number of show methods was under some limit.