Reinstate commons-logging exclusion on infinispan-spring4

Infinispan 8.0.2 has moved to Log4J2 for all logging, but still has a
transitive dependency on commons-logging. This resulted in
commons-logging 1.1 being on the classpath of spring-boot-docs which
breaks its javadoc generation.

Closes gh-4727

spring-boot-dependencies/pom.xml

@@ -1554,6 +1554,10 @@
 				<artifactId>infinispan-spring4</artifactId>
 				<version>${infinispan.version}</version>
 				<exclusions>
+					<exclusion>
+						<groupId>commons-logging</groupId>
+						<artifactId>commons-logging</artifactId>
+					</exclusion>
 					<exclusion>
 						<groupId>org.apache.logging.log4j</groupId>
 						<artifactId>log4j-core</artifactId>