Do not test 5.10.x without the LR fix

Author: jeeminso

tests/bwc/test_rolling_upgrade.py

@@ -41,7 +41,6 @@
     UpgradePath('5.7.x', '5.8.x'),
     UpgradePath('5.8.x', '5.9.x'),
     UpgradePath('5.9.x', '5.10.x'),
-    UpgradePath('5.10.x', '5.10'),
     UpgradePath('5.10', 'latest-nightly'),
 )