Remove duplicated dependency in spring-boot-docs

See gh-18092

Author: dreis2211

spring-boot-project/spring-boot-docs/pom.xml

@@ -842,11 +842,6 @@
 			<artifactId>spring-data-jdbc</artifactId>
 			<optional>true</optional>
 		</dependency>
-		<dependency>
-			<groupId>org.springframework.data</groupId>
-			<artifactId>spring-data-jdbc</artifactId>
-			<optional>true</optional>
-		</dependency>
 		<dependency>
 			<groupId>org.springframework.data</groupId>
 			<artifactId>spring-data-jpa</artifactId>