Chore: update dodona-tested dockerfile

Author: dodona-server

dodona-tested.dockerfile

@@ -111,7 +111,9 @@ RUN <<EOF
 
     # Exercise dependencies
     pip install --no-cache-dir --upgrade \
-      numpy==2.3.5
+      numpy==2.3.5 \
+      pandas==3.0.1 \
+      openpyxl==3.1.5
 
     # Clean up caches
     apt-get clean