Revert "Bump HikariCP from 3.4.3 to 3.4.4 in /modules/spock" (#2686)

Author: rnorth

modules/spock/build.gradle

@@ -12,7 +12,7 @@ dependencies {
     testCompile project(':mysql')
     testCompile project(':postgresql')
 
-    testCompile 'com.zaxxer:HikariCP:3.4.4'
+    testCompile 'com.zaxxer:HikariCP:3.4.3'
     testCompile 'org.apache.httpcomponents:httpclient:4.5.12'
 
     testRuntime 'org.postgresql:postgresql:42.2.12'