[extractor/nitter] Update Nitter instance list

[OIRNOIR]

IMPORTANT: PRs without the template will be CLOSED

Description of your pull request and other information

Updated the Nitter instance list slightly
Nitter.ca has been dead for months now, added my preferred instance n.l5.ca.

Fixes #

Template

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[OIRNOIR]

Here's the story behind my adding n.l5.ca to yt-dlp:
I used to use nitter.mint.lgbt (already in the list) but that has been getting slower recently so I went to this list to find a faster one. I ended up settling on n.l5.ca. The only issue is that it isn't on this list so I need to replace the name with twitter or some other nitter host before I download.

[pukkandan]

Since you are editing this, pls sync the list with https://github.com/zedeus/nitter/wiki/Instances

[OIRNOIR]

Done!