[Java] Upgrade to Agrona 1.2.0.

Author: mjpt777

build.gradle

@@ -34,7 +34,7 @@ def hamcrestVersion = '2.2'
 def mockitoVersion = '3.2.4'
 def junitVersion = '5.6.0-RC1'
 def jmhVersion = '1.22'
-def agronaVersion = '1.1.0'
+def agronaVersion = '1.2.0'
 
 def sbeGroup = 'uk.co.real-logic'
 def sbeVersion = file('version.txt').text.trim()