OLMIS-6066: Upgrade gradle to 5.2+ version

Author: Łukasz Lewczyński

README.md

@@ -50,7 +50,7 @@ Most interactions should occur through docker-compose.
 ## Tech
 
 - JDK 1.8+
-- Gradle 4.10+
+- Gradle 5.2+
 - Node 8+
 - PSQL 10+
 - RAML-Cop 5

install_gradle.sh

@@ -1,6 +1,6 @@
 #!/bin/sh
 
-wget -O gradle.zip http://services.gradle.org/distributions/gradle-4.10.2-bin.zip
+wget -O gradle.zip http://services.gradle.org/distributions/gradle-5.2.1-bin.zip
 unzip gradle.zip
 rm gradle.zip
-ln -s "$HOME/gradle-4.10.2/bin/gradle" /sbin/gradle
+ln -s "$HOME/gradle-5.2.1/bin/gradle" /sbin/gradle