Make gretty samples compatible with logback 1.2.9

Explicitly reference the logback.xml file to prevent gretty from configuring the defaults using groovy.

spring-session-samples/spring-session-sample-javaconfig-custom-cookie/spring-session-sample-javaconfig-custom-cookie.gradle

@@ -21,4 +21,5 @@ dependencies {
 
 gretty {
 	jvmArgs = ['-Dspring.profiles.active=embedded-redis']
+	logbackConfigFile = "src/main/resources/logback.xml"
 }

spring-session-samples/spring-session-sample-javaconfig-hazelcast/spring-session-sample-javaconfig-hazelcast.gradle

@@ -21,3 +21,7 @@ dependencies {
 
 	integrationTestCompile seleniumDependencies
 }
+
+gretty {
+	logbackConfigFile = "src/main/resources/logback.xml"
+}

spring-session-samples/spring-session-sample-javaconfig-jdbc/spring-session-sample-javaconfig-jdbc.gradle

@@ -17,3 +17,7 @@ dependencies {
 
 	integrationTestCompile seleniumDependencies
 }
+
+gretty {
+	logbackConfigFile = "src/main/resources/logback.xml"
+}

spring-session-samples/spring-session-sample-javaconfig-redis/spring-session-sample-javaconfig-redis.gradle

@@ -21,4 +21,5 @@ dependencies {
 
 gretty {
 	jvmArgs = ['-Dspring.profiles.active=embedded-redis']
+	logbackConfigFile = "src/main/resources/logback.xml"
 }

spring-session-samples/spring-session-sample-javaconfig-rest/spring-session-sample-javaconfig-rest.gradle

@@ -23,4 +23,5 @@ dependencies {
 gretty {
 	jvmArgs = ['-Dspring.profiles.active=embedded-redis']
 	servletContainer = 'tomcat9'
+	logbackConfigFile = "src/main/resources/logback.xml"
 }

spring-session-samples/spring-session-sample-javaconfig-security/spring-session-sample-javaconfig-security.gradle

@@ -25,4 +25,5 @@ dependencies {
 
 gretty {
 	jvmArgs = ['-Dspring.profiles.active=embedded-redis']
+	logbackConfigFile = "src/main/resources/logback.xml"
 }

spring-session-samples/spring-session-sample-misc-hazelcast/spring-session-sample-misc-hazelcast.gradle

@@ -16,3 +16,7 @@ dependencies {
 
 	integrationTestCompile seleniumDependencies
 }
+
+gretty {
+	logbackConfigFile = "src/main/resources/logback.xml"
+}

spring-session-samples/spring-session-sample-xml-jdbc/spring-session-sample-xml-jdbc.gradle

@@ -17,3 +17,7 @@ dependencies {
 
 	integrationTestCompile seleniumDependencies
 }
+
+gretty {
+	logbackConfigFile = "src/main/resources/logback.xml"
+}

spring-session-samples/spring-session-sample-xml-redis/spring-session-sample-xml-redis.gradle

@@ -21,4 +21,5 @@ dependencies {
 
 gretty {
 	jvmArgs = ['-Dspring.profiles.active=embedded-redis']
+	logbackConfigFile = "src/main/resources/logback.xml"
 }