Fix for ensure that numCorrect is calculated properly when editing new Radio Widgets (#2317)

## Summary:
Radio questions set to Multiple Select and "Specify Number Correct" set to true were not actually having the text update accordingly in the Editor. This PR fixes the numCorrect calculation so that new widgets with these values will have numCorrect calculated properly.

Issue: LEMS-2921

## Test plan:
- manual testing

Author: SonicScrewdriver

Reviewers: mark-fitzgerald

Required Reviewers:

Approved By: mark-fitzgerald

Checks: ✅ 8 checks were successful

Pull Request URL: #2317

Author: SonicScrewdriver

.changeset/quiet-clouds-design.md

@@ -0,0 +1,5 @@
+---
+"@khanacademy/perseus-editor": patch
+---
+
+Bugfix to ensure numCorrect is calculated correctly while in Radio Editor

packages/perseus-editor/src/widgets/radio/editor.tsx

@@ -174,6 +174,9 @@ class RadioEditor extends React.Component<RadioEditorProps> {
             numCorrect: deriveNumCorrect({
                 ...this.props,
                 choices,
+                // When deriving numCorrect, we don't want to pass the current value,
+                // as it has changed.
+                numCorrect: undefined,
             }),
         });
     };
@@ -279,7 +282,12 @@ class RadioEditor extends React.Component<RadioEditorProps> {
             displayCount,
             hasNoneOfTheAbove,
             deselectEnabled,
-            numCorrect: deriveNumCorrect(this.props),
+            numCorrect: deriveNumCorrect({
+                ...this.props,
+                // When deriving numCorrect, we don't want to pass the current value,
+                // as it has changed.
+                numCorrect: undefined,
+            }),
         };
     }