[SW-1702] Upgrade to Gradle 5.6.4 (#1607)
[SW-1702] Upgrade to Gradle 5.6.4 (#1607)


(cherry picked from commit 6fa71b8053630afd931b1abbba018cec70e92275)

h2oai/sparkling-water,h2oai/sparkling-water,h2oai/sparkling-water,h2oai/sparkling-water