Upgrade to GemFire 8.2.8

Closes gh-11746

Author: wilkinsona

spring-boot-dependencies/pom.xml

@@ -75,7 +75,7 @@
 		<flyway.version>3.2.1</flyway.version>
 		<freemarker.version>2.3.27-incubating</freemarker.version>
 		<elasticsearch.version>2.4.6</elasticsearch.version>
-		<gemfire.version>8.2.7</gemfire.version>
+		<gemfire.version>8.2.8</gemfire.version>
 		<glassfish-el.version>3.0.0</glassfish-el.version>
 		<gradle.version>2.9</gradle.version>
 		<groovy.version>2.4.13</groovy.version>