Treat Maven artifacts with bundle packaging as jars

Previously, LocalM2Resource used the pom's packaging configuration to
determine the suffix of the file that it should look for, e.g. if
the pom's packaging was jar, it would look for a file with a .jar
suffix in artifactExists(). This logic fails for artifacts with bundle
packaging as it would look for a .bundle file rather than a .jar file,
fail to find the file, and incorrectly report that the artifact does not
exist.

This commit updates LocalM2Resource to look for a file with a .jar
suffix when the packaging configuration in the pom is bundle.