Correct permissions of omniauth-jwt

What does this MR do?

omniauth-jwt 0.0.2 installs omniauth/strategies/jwt.rb with mode 0600.

This is probably correct on the authors machine, but prevents us from using it reliably as we install files as the root user but run them as the git user.

Here we add a targeted chown to ensure the files are readable every time.

Checklist

See Definition of done.

• Change added to CHANGELOG.md. Not applicable for Documentation changes and minor changes.
• Documentation created/updated
• Tests added
• Integration tests added to GitLab QA, if applicable
• MR targeting master branch
• MR has a green pipeline on GitLab.com

Reviewer Checklist

In addition to above, reviewer must:

• Pipeline is green on dev.gitlab.org if the change is not touching documentation or internal cookbooks

References

omniauth-jwt was added to gitlab-ce with https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/17774

Report upstream https://github.com/mbleigh/omniauth-jwt/issues/6

Closes gitlab-qa#212 (closed)