Remove duplicated message on collapsed MR diff for being too large

Summary

Collapsed diffs for being too large are showing the same message twice.

Example MR: azanelli-lab/bug-mr-display-3590!2 (diffs)

Steps to reproduce

1. Create an MR with one file having 3000 changes.
2. Check the MR changes tab.
3. The message should be displayed twice.

Example Project

azanelli-lab/bug-mr-display-3590!2 (diffs)

What is the current bug behavior?

Shows the message twice.

What is the expected correct behavior?

Shows the message once.