SpringBoot Build against Oracle JDBC driver variant ojdbc11

Oracle provides multiple variants of their jdbc driver and connection pool, each targeting a different JDK baseline.

From https://www.oracle.com/database/technologies/maven-central-guide.html#DIY

ojdbc8: Supports JDBC 4.2 spec and for use with JDK8 and JDK11 ojdbc11: Supports JDBC 4.3 spec and for use with JDK11 and JDK17 ucp11: The Java Universal Connection Pool for Oracle Database compiled with JDK11

This PR updates spring-boot to build against the 11 variants.

Also, start.spring.io still provides the ojdbc8 dependency.

<dependency>
      <groupId>com.oracle.database.jdbc</groupId>
      <artifactId>ojdbc8</artifactId>
      <scope>runtime</scope>
</dependency>

Comment From: mhalbritter

Thank you!