Remove deadlink

[joshdavham]

On the Introduction page of the addon docs, the first link (https://t-cool.github.io/anki-addon-docs-ja/) was dead, so I removed it.

Let me know if you have any questions 👍

[abdnh]

Can we use an archive link instead? https://web.archive.org/web/20220707064637/https://t-cool.github.io/anki-addon-docs-ja/

[joshdavham]

@abdnh

That's definitely a possibility, but in my opinion, between

1. Replacing a deadlink with an archive of an outdated translation and
2. Just removing the deadlink

I personally favor the latter.

[GithubAnon0000]

For people that do not know english, an outdated manual in their native language might be better than an up to date manual that is in a non-native language.

Though arguably it might not matter if
a) the translated manual is really far behind (and thus, most things you can find there don't even apply to the latest anki) and
b) there are enough commonly known translation tools, that can translate from english to the target language accurately.