[GR-62101] Ensure users see final bundle output directories in build-output.

[graalvmbot]

Running native-image --bundle-apply=test.nib without this fix we see:

...
------------------------------------------------------------------------------------------------------------------------
                        0.8s (5.5% of total time) in 50 GCs | Peak RSS: 2.08GB | CPU load: 12.66
------------------------------------------------------------------------------------------------------------------------
Build artifacts:
 /tmp/bundleRoot-17638292161372705685/output/default/gdb-debughelpers.py (debug_info)
 /tmp/bundleRoot-17638292161372705685/output/default/jdk.httpserver (executable)
 /tmp/bundleRoot-17638292161372705685/output/default/jdk.httpserver.debug (debug_info)
 /tmp/bundleRoot-17638292161372705685/output/default/sources (debug_info)
========================================================================================================================
Finished generating 'jdk.httpserver' in 14.4s.

Native Image Bundles: Bundle build output written to /home/pwoegere/OLabs/bitbucket/main/graal/substratevm/test.output

with the fix we see:

...
------------------------------------------------------------------------------------------------------------------------
                        0.9s (5.8% of total time) in 50 GCs | Peak RSS: 1.96GB | CPU load: 12.10
------------------------------------------------------------------------------------------------------------------------
Build artifacts:
 /home/pwoegere/OLabs/bitbucket/main/graal/substratevm/test.output/default/gdb-debughelpers.py (debug_info)
 /home/pwoegere/OLabs/bitbucket/main/graal/substratevm/test.output/default/jdk.httpserver (executable)
 /home/pwoegere/OLabs/bitbucket/main/graal/substratevm/test.output/default/jdk.httpserver.debug (debug_info)
 /home/pwoegere/OLabs/bitbucket/main/graal/substratevm/test.output/default/sources (debug_info)
========================================================================================================================
Finished generating 'jdk.httpserver' in 15.4s.

Native Image Bundles: Bundle build output written to /home/pwoegere/OLabs/bitbucket/main/graal/substratevm/test.output