Standardize shared resource links

[brchristian]

Currently there is a difference between new_resource_links and edit_resource_links. Namely, in one the Cancel button is of class: 'button' and in the other the Cancel button is of class: 'btn btn-primary'.

Based on how they render in the browser, I assume that new_resource_links (class: 'button') is correct, as it looks like this:

Whereas the shared_resource_links (class: 'btn btn-primary') looks like this, with a weird visual bug:

After this commit, which changes shared_resource_links to be similar to new_resource_links, the visual behavior is fixed and it looks like this:

[jacobherrington]

Thanks @brchristian!

[kennyadsl]

👍

I also have the feeling that we can remove class: 'btn btn-primary' from all the <button> elements since it looks like they already have the same css. But of course this should be handled into another PR.