og4j-over-slf4j is an adapter JAR that allows projects to migrate from log4j to slf4j (Log4j Bridge) :
SLF4J ship with a module called log4j-over-slf4j . It allows log4j users to migrate existing applications to SLF4J without changing a single line of code but simply by replacing the log4j.jar file with log4j-over-slf4j.jar , as described below.
The jar is (I can only guess) a holdover from when Jenkins used to use log4j and migrated to slf4j.
From http://slf4j.org/log4shell.html:
If you are using log4j-over-slf4j.jar in conjunction with the SLF4J API, you are safe unless the underlying implementation is log4j 2.x.
Which would mean you just need to ensure the actual log4j 2.x jar is not there.