Bump org.hibernate:hibernate-entitymanager

Bumps [org.hibernate:hibernate-entitymanager](https://github.com/hibernate/hibernate-orm) from 5.6.14.Final to 5.6.15.Final.
- [Release notes](https://github.com/hibernate/hibernate-orm/releases)
- [Changelog](https://github.com/hibernate/hibernate-orm/blob/5.6.15/changelog.txt)
- [Commits](hibernate/hibernate-orm@5.6.14...5.6.15)

---
updated-dependencies:
- dependency-name: org.hibernate:hibernate-entitymanager
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

build.gradle

@@ -16,7 +16,7 @@ dependencies {
     compile 'org.codehaus.groovy:groovy-all:2.5.9'
     compile 'javax.json:javax.json-api:1.1.4'
 
-    compile 'org.hibernate:hibernate-entitymanager:5.6.14.Final'
+    compile 'org.hibernate:hibernate-entitymanager:5.6.15.Final'
 
     testCompile 'org.spockframework:spock-core:1.3-groovy-2.5'
     testCompile 'junit:junit:4.13.2'