Remove blanks before the extension

[torredipisa]

Hi
Cannot understand how remove any blank char before the extension of a file.
For example: aaaaaaa .dng
I would reach: aaaaaaa.dng
Any suggestion?
Thank you very much.
Fabio

[Luuk]

Remove(5) can use "Trim" to remove any leading and/or trailing spaces.
Replace(3) could use a "Replace" like \end\ | (without really needing the "|").
RegEx(1) with a v2 checkmark needs a "Match" like \ +$ (without really needing the "\").