Add sample for OAuth2 RestClient interceptor

Closes gh-294

servlet/spring-boot/java/oauth2/restclient/build.gradle

@@ -0,0 +1,28 @@
+plugins {
+	alias(libs.plugins.org.springframework.boot)
+	alias(libs.plugins.io.spring.dependency.management)
+	id "nebula.integtest" version "8.2.0"
+	id 'java'
+}
+
+repositories {
+	mavenCentral()
+	maven { url "https://repo.spring.io/milestone" }
+	maven { url "https://repo.spring.io/snapshot" }
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-oauth2-client'
+	implementation 'org.springframework.boot:spring-boot-starter-thymeleaf'
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	implementation 'org.thymeleaf.extras:thymeleaf-extras-springsecurity6'
+
+	testImplementation 'org.springframework.boot:spring-boot-starter-test'
+	testImplementation 'org.springframework.security:spring-security-test'
+	testImplementation 'com.squareup.okhttp3:mockwebserver'
+}
+
+
+tasks.withType(Test).configureEach {
+	useJUnitPlatform()
+}