Fix: Prevent state mutation in fetchRevisionsPromise function

- Avoid direct mutation of `course.revisions` by creating a new object with updated revisions.
- Ensures compliance with Redux's immutability rules to avoid errors during state updates.

app/assets/javascripts/actions/revisions_actions.js

@@ -1,4 +1,3 @@
-
 import {
   RECEIVE_REVISIONS,
   REVISIONS_LOADING,
@@ -35,12 +34,19 @@ const fetchAllArticles = async (course) => {
 
 const fetchRevisionsPromise = async (course, users, last_date, dispatch) => {
   const { revisions, last_date: new_last_date } = await fetchRevisionsFromUsers(course, users, 7, last_date);
-  course.revisions = sortRevisionsByDate(revisions);
 
-  // we don't await this. When the assessments/references get laoded, the action is dispatched
+  // Create a new course object with updated revisions
+  const updatedCourse = {
+    ...course,
+    revisions: sortRevisionsByDate(revisions),
+  };
+
+  // we don't await this. When the assessments/references get loaded, the action is dispatched
   fetchRevisionsAndReferences(revisions, dispatch);
-  return { course, last_date: new_last_date };
+
+  return { course: updatedCourse, last_date: new_last_date };
 };
+
 const fetchRevisionsCourseSpecificPromise = async (course, users, last_date, dispatch, articles) => {
   const trackedArticles = new Set(
     articles.filter(article => article.tracked).map(article => article.title)