Previously, the ordering of the entries in an archive produced by
BootJar was different to the ordering of the entries in an archive
produced by BootWar. The latter placed application classes before
any nested jars, whereas the former was the other way around.

This commit updates BootJar to use the same ordering as BootWar and
adds tests to verify that the ordering is the following:

1. Loader classes
2. Application classes (BOOT-INF/classes or WEB-INF/classes)
3. Nested jars (BOOT-INF/lib or WEB-INF/lib)
4. Provided nested jars in a war (WEB-INF/lib-provided)

The tests also verify that the position of a library is not affected
by it requiring unpacking.

See gh-11695
See gh-11696