Bug 1776512: Fix failing test CLOSED TREE

Differential Revision: https://phabricator.services.mozilla.com/D150287

tools/lint/test/test_updatebot.py

@@ -11,7 +11,7 @@ def test_basic(lint, paths):
     i = 0
     assert results[i].level == "error"
     assert "cargo-mismatch.yaml" in results[i].relpath
-    assert "was not found in Cargo.lock" in results[i].message
+    assert "wasn't found in Cargo.lock" in results[i].message
 
     i += 1
     assert results[i].level == "error"