chore: update maven compile plugin to match JDK version

backend/application.yml

@@ -0,0 +1,21 @@
+spring:
+  datasource:
+    url: ${DB_URL}
+    username: ${DB_USER}
+    password: ${DB_PASSWORD}
+    driver-class-name: org.postgresql.Driver
+
+  jpa:
+    hibernate:
+      ddl-auto: update
+    show-sql: true
+    properties:
+      hibernate:
+        dialect: org.hibernate.dialect.PostgreSQLDialect
+        format_sql: true
+
+  application:
+    name: wesal
+
+server:
+  port: 8080

backend/pom.xml

@@ -28,6 +28,8 @@
 	</scm>
 	<properties>
 		<java.version>21</java.version>
+		<maven.compiler.source>21</maven.compiler.source>
+		<maven.compiler.target>21</maven.compiler.target>
 	</properties>
 	<dependencies>
 		<dependency>
@@ -96,7 +98,17 @@
 				<groupId>org.springframework.boot</groupId>
 				<artifactId>spring-boot-maven-plugin</artifactId>
 			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-compiler-plugin</artifactId>
+				<version>3.13.0</version>
+				<configuration>
+					<source>21</source>
+					<target>21</target>
+					<release>21</release>
+				</configuration>
+			</plugin>
 		</plugins>
 	</build>
 
-</project>
+</project>