Remove dependency management for cassandra-driver-dse

The 3.1 release of the Cassandra Driver does not include the
cassandra-driver-dse module.

See gh-5835

spring-boot-dependencies/pom.xml

@@ -571,25 +571,6 @@
 				<artifactId>cassandra-driver-core</artifactId>
 				<version>${cassandra-driver.version}</version>
 			</dependency>
-			<dependency>
-				<groupId>com.datastax.cassandra</groupId>
-				<artifactId>cassandra-driver-dse</artifactId>
-				<version>${cassandra-driver.version}</version>
-				<exclusions>
-					<exclusion>
-						<groupId>org.slf4j</groupId>
-						<artifactId>slf4j-log4j12</artifactId>
-					</exclusion>
-					<exclusion>
-						<groupId>log4j</groupId>
-						<artifactId>log4j</artifactId>
-					</exclusion>
-					<exclusion>
-						<groupId>com.google.guava</groupId>
-						<artifactId>guava</artifactId>
-					</exclusion>
-				</exclusions>
-			</dependency>
 			<dependency>
 				<groupId>com.datastax.cassandra</groupId>
 				<artifactId>cassandra-driver-mapping</artifactId>