Switch for_parameterize to for_parametrize

[alanbato]

From the authors that brought you the controversial #3159...

Change the naming of for_parameterize to for_parametrize in order to comply with the current convention on naming. This should make the whole codebase as of now have the parametrize spelling.
🐍

Now in theaters close to your location

[coveralls]

Coverage remained the same at 92.628% when pulling ef7df8f on alanbato:typo_for_parametrize into f2fb841 on pytest-dev:master.

[nicoddemus]

Thanks! 😁