maven: Use actual file name for jar file type test

Since we care about the file and not just the artifact object, we check
the file name for ending in ".jar" (jar extension) instead of relying
on the artifact reporting the "jar" type.

Fixes #5349

Signed-off-by: BJ Hargrave <bj@hargrave.dev>

maven/bnd-maven-plugin/src/main/java/aQute/bnd/maven/plugin/AbstractBndMavenPlugin.java

@@ -302,8 +302,7 @@ public void execute() throws MojoExecutionException, MojoFailureException {
 					builder.updateModified(cpeJar.lastModified(), cpe.getPath());
 					buildpath.add(cpeJar);
 				} else {
-					if (!artifact.getType()
-						.equals("jar")) {
+					if (!cpe.getName().endsWith(".jar")) {
 						/*
 						 * Check if it is a valid zip file. We don't create a
 						 * Jar object here because we want to avoid the cost of