Remove redundant targetCompatibility from gradle buildscript

See gh-330

initializr-generator/src/main/resources/templates/starter-build.gradle

@@ -27,8 +27,8 @@ apply plugin: 'war'<% } %>
 	baseName = '${artifactId}'
 	version = '${version}'
 }
+
 sourceCompatibility = ${javaVersion}
-targetCompatibility = ${javaVersion}
 
 repositories {
 	mavenCentral()<% if (repositories) { repositories.each { key, repo -> %>

initializr-generator/src/test/groovy/io/spring/initializr/test/generator/GradleBuildAssert.groovy

@@ -57,7 +57,6 @@ class GradleBuildAssert {
 
 	GradleBuildAssert hasJavaVersion(String javaVersion) {
 		contains("sourceCompatibility = $javaVersion")
-		contains("targetCompatibility = $javaVersion")
 	}
 
 	GradleBuildAssert hasSnapshotRepository() {

initializr-generator/src/test/resources/project/gradle/bom-property-build.gradle.gen

@@ -20,8 +20,8 @@ jar {
 	baseName = 'demo'
 	version = '0.0.1-SNAPSHOT'
 }
+
 sourceCompatibility = 1.8
-targetCompatibility = 1.8
 
 repositories {
 	mavenCentral()

initializr-generator/src/test/resources/project/gradle/compile-only-dependency-build.gradle.gen

@@ -20,8 +20,8 @@ jar {
 	baseName = 'demo'
 	version = '0.0.1-SNAPSHOT'
 }
+
 sourceCompatibility = 1.8
-targetCompatibility = 1.8
 
 repositories {
 	mavenCentral()

initializr-generator/src/test/resources/project/gradle/version-override-build.gradle.gen

@@ -20,8 +20,8 @@ jar {
 	baseName = 'demo'
 	version = '0.0.1-SNAPSHOT'
 }
+
 sourceCompatibility = 1.8
-targetCompatibility = 1.8
 
 repositories {
 	mavenCentral()

initializr-generator/src/test/resources/project/groovy/standard/build.gradle.gen

@@ -20,8 +20,8 @@ jar {
 	baseName = 'demo'
 	version = '0.0.1-SNAPSHOT'
 }
+
 sourceCompatibility = 1.8
-targetCompatibility = 1.8
 
 repositories {
 	mavenCentral()

initializr-generator/src/test/resources/project/groovy/war/build.gradle.gen

@@ -21,8 +21,8 @@ war {
 	baseName = 'demo'
 	version = '0.0.1-SNAPSHOT'
 }
+
 sourceCompatibility = 1.8
-targetCompatibility = 1.8
 
 repositories {
 	mavenCentral()

initializr-generator/src/test/resources/project/java/standard/build.gradle.gen

@@ -20,8 +20,8 @@ jar {
 	baseName = 'demo'
 	version = '0.0.1-SNAPSHOT'
 }
+
 sourceCompatibility = 1.8
-targetCompatibility = 1.8
 
 repositories {
 	mavenCentral()

initializr-generator/src/test/resources/project/java/war/build.gradle.gen

@@ -21,8 +21,8 @@ war {
 	baseName = 'demo'
 	version = '0.0.1-SNAPSHOT'
 }
+
 sourceCompatibility = 1.8
-targetCompatibility = 1.8
 
 repositories {
 	mavenCentral()

initializr-generator/src/test/resources/project/kotlin/standard/build.gradle.gen

@@ -24,8 +24,8 @@ jar {
 	baseName = 'demo'
 	version = '0.0.1-SNAPSHOT'
 }
+
 sourceCompatibility = 1.8
-targetCompatibility = 1.8
 
 repositories {
 	mavenCentral()

initializr-generator/src/test/resources/project/kotlin/war/build.gradle.gen

@@ -25,8 +25,8 @@ war {
 	baseName = 'demo'
 	version = '0.0.1-SNAPSHOT'
 }
+
 sourceCompatibility = 1.8
-targetCompatibility = 1.8
 
 repositories {
 	mavenCentral()