Refactor to use update!

Replaced update with update! to raise an exception in case of validation
failure, as suggested by the Rails/SaveBang RuboCop rule. This ensures that any
issues with updating the problem_report are explicitly handled by raising an
exception.

app/controllers/anonymous_feedback/problem_reports_controller.rb:77:24: C:
[Correctable] Rails/SaveBang: Use update! instead of update if the return value
is not checked. (https://rails.rubystyle.guide#save-bang)

        problem_report.update(review_attrs)
                       ^^^^^^

app/controllers/anonymous_feedback/problem_reports_controller.rb

@@ -74,9 +74,9 @@ def mark_supplied_reports_as_reviewed_and_spam
 
         review_attrs = { reviewed: true, marked_as_spam: }
 
-        problem_report.update(review_attrs)
+        problem_report.update!(review_attrs)
       end
-    rescue ActiveRecord::RecordNotFound
+    rescue ActiveRecord::RecordNotFound, ActiveRecord::RecordInvalid
       false
     end