Add missing file pattern to CODEOWNERS

[galbwe]

Associated Issue

closes #46

Implemented Solution

According to github's docs, the CODEOWNERS file should control who is automatically added as a PR reviewer.

The CODEOWNERS file is missing a filepath before the github username, which I think is the reason no reviewers are added automatically to PRs. You can verify by opening any file in this repo in the github ui. You should see a lock icon with hover text telling you the codeowner for that file

Here is an example from a different repo where the CODEOWNERS file is correct:

[welcome[bot]]

Thanks for opening this pull request for myanimelist-cli! Please wait shortly for someone to review.

[ghost]

👇 Click on the image for a new way to code review

- Make big changes easier — review code in small groups of related files - Know where to start — see the whole change at a glance - Take a code tour — explore the change with an interactive tour - Make comments and review — all fully sync’ed with github [Try it now!](https://app.codesee.io/r/reviews?pr=47&src=https%3A%2F%2Fgithub.com%2Fjmakhack%2Fmyanimelist-cli)

Legend

[welcome[bot]]

Congrats on merging your first pull request to myanimelist-cli! Please give our project a star if you like what we are building here.