Upgrade to Tomcat 8.5.4 & remove tomcat-juli

Upgrade the managed Tomcat dependency to 8.5.4 and remove `tomcat-juli`
since it's now included in `tomcat-embed-core`.

Fixes gh-6192

spring-boot-samples/spring-boot-sample-actuator/build.gradle

@@ -20,6 +20,8 @@ apply plugin: 'eclipse'
 apply plugin: 'idea'
 apply plugin: 'spring-boot'
 
+ext['h2.version'] = '1.4.192'
+
 jar {
 	baseName = 'spring-boot-sample-actuator'
 }
@@ -45,7 +47,7 @@ dependencies {
 	compile("org.springframework.boot:spring-boot-starter-jdbc")
 	compile("org.springframework.boot:spring-boot-starter-security")
 	compile("org.springframework.boot:spring-boot-starter-web")
-	compile("com.h2database:h2")
+	compile group:"com.h2database", name:"h2", version:property('h2.version')
 
 	testCompile("org.springframework.boot:spring-boot-starter-test")
 
@@ -64,4 +66,4 @@ task wrapper(type: Wrapper) {
 
 springBoot {
 	buildInfo()
-}
+}