code: @Deprecated
      public MergeRequest updateMergeRequest(Object projectIdOrPath, Integer mergeRequestIid, String sourceBranch, String targetBranch, String title, String description,
              Integer assigneeId) throws GitLabApiException {
  
          Form formData = new Form();
          addFormParam(formData, "source_branch", sourceBranch, false);
          addFormParam(formData, "target_branch", targetBranch, false);
          addFormParam(formData, "title", title, false);
          addFormParam(formData, "description", description, false);
          addFormParam(formData, "assignee_id", assigneeId, false);
  
          return updateMergeRequest(projectIdOrPath, mergeRequestIid, formData);
      }
docs: Updates an existing merge request. You can change branches, title, or even close the MR.
  
  <p>NOTE: GitLab API V4 uses IID (internal ID), V3 uses ID to identify the merge request.</p>
  
  <pre><code>GitLab Endpoint: PUT /projects/:id/merge_requests/:merge_request_iid</code></pre>
  
  @param projectIdOrPath the project in the form of an Integer(ID), String(path), or Project instance
  @param mergeRequestIid the internal ID of the merge request to update
  @param sourceBranch the source branch
  @param targetBranch the target branch
  @param title the title for the merge request
  @param description the description of the merge request
  @param assigneeId the Assignee user ID, optional
  @return the updated merge request
  @throws GitLabApiException if any exception occurs
  @deprecated as of release 4.4.3