Bug: Link content toast notification should not be displaying

[jmakowski1123]

The linked content toast notification should not be displaying when I create a new content block, either from library home or from the collection page.

[bradenmacdonald]

@navinkarkera The fix for #1435 seems to have introduced a regression that whenever a component is added to a library (e.g. add a Text component from the Library Home page), it shows a "Content linked successfully" toast. (Even when no collection is involved.)

Can you please look into that? And as mentioned above + on Slack we actually don't ever need that toast so it should be removed everywhere. It wasn't in the original specs for #1173

CC @rpenido

https://openedx.slack.com/archives/C06JG6RFE4V/p1731022665501119

[navinkarkera]

@bradenmacdonald Got it. Created this PR: #1490 to fix it.