Rename oauth2-oidc-client starter in sample

Fixup sample POM following rename of the oauth2-oidc-client starter.

See spring-projectsgh-14951

Author: philwebb

spring-boot-samples/spring-boot-sample-oauth2-client/pom.xml

@@ -18,7 +18,7 @@
 		<!-- Compile -->
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
-			<artifactId>spring-boot-starter-oauth2-oidc-client</artifactId>
+			<artifactId>spring-boot-starter-oauth2-client</artifactId>
 		</dependency>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>