build: update GH actions-comment-pull-request to v2.3.1

Signed-off-by: deadprogram <ron@hybridgroup.com>

.github/workflows/sizediff.yml

@@ -88,7 +88,7 @@ jobs:
       - name: Comment contents
         run: cat comment.txt
       - name: Add comment
-        uses: thollander/actions-comment-pull-request@v2
+        uses: thollander/actions-comment-pull-request@v2.3.1
         with:
           filePath: comment.txt
           comment_tag: sizediff