Fix typo "extenstion" in Modules/xxlimited.c

[michaelbnewman]

Fix typo extenstion to extensions in Modules/xxlimited.c

Methodology

$ brew install typos-cli
$ typos xxlimited.c 
error: `extenstions` should be `extensions`
    ╭▸ xxlimited.c:636:66
    │
636 │ // Information that CPython uses to prevent loading incompatible extenstions
    ╰╴                                                                 ━━━━━━━━━━━

[StanFromIreland]

Hi! As noted in the devguide we generally only accept PRs with fixes in documentation. Sorry, but I'm closing.