And use your own question above as test.
But it will be altered on quoting, so we need fenced quotes:
["this is random text that will be removed along with the quotation marks and brackets."]
I copied and pasted you quotes and it works. So how did you get those particular quotation marks? I will remove all the paragraph markers and then use your syntax. Should work.
On this site it is a feature:
In writer it depends on your locale while typing…
If in doubt I just copy from my text and paste to the search box ( there are several hyphens and I know of 5 variants of space in UniCode )
Press Ctrl+H (Find and Replace)
enter “.*”