Delete the deployment part of `tech.kazu634.com`.

This commit refs #114.
Delete the unnecessary `authorized_keys`.

This commit refs #114.
Modify the `tech` nginx configuration to redirect to `blog.kazu634.com`.

This commit refs #114.
Merge pull request #114 from kazu634/id/114

[nginx] tech.kazu634.comのサイトをblog.kazu634.comにリダイレクトする