Hello,
You can edit your robots.txt file and delete the following code:
User-agent: *
Disallow: /calendar/action~posterboard/
Disallow: /calendar/action~agenda/
Disallow: /calendar/action~oneday/
Disallow: /calendar/action~month/
Disallow: /calendar/action~week/
Disallow: /calendar/action~stream/
However, doing this will slow down your site and will affect the performance.
Take Care