feat: ability to add email to recipients list by clicking enter (#760)

I encountered so many times now that I send by email, which I use 99% of the time, it didnt got send, because the mail was not accepted when pressing enter. 

Also because no confirmation mail is send, i never knew it arrived. Ill work on that code later, but adding enter to that field, will help a lot!

frontend/src/components/upload/modals/showCreateUploadModal.tsx

@@ -410,7 +410,7 @@ const CreateUploadModalBody = ({
                     {...form.getInputProps("recipients")}
                     onKeyDown={(e: React.KeyboardEvent<HTMLInputElement>) => {
                       // Add email on comma or semicolon
-                      if (e.key === "," || e.key === ";") {
+                      if (e.key === "Enter" || e.key === "," || e.key === ";") {
                         e.preventDefault();
                         const inputValue = (
                           e.target as HTMLInputElement