use "name" field from the product template as the default file name instead of "tile"

[crhntr]

Is your feature request related to a problem? Please describe.

I have been reading tile build scripts and found most scripts do this kind of thing.

We should have a better default than tile-"${TILE_VERSION}.pivotal. I found that this team could reduce the code after kiln bake in their script if we do something similar to what they are doing.

https://github.com/pivotal/cryogenics-concourse-tasks/blob/a4109ac940e5adf5cfa7d4f806c915b3393bd215/tasks/kiln-bake-task/task.sh

Another option would be to have configuration in the Kilnfile for this. Preferably the Kilnfile would allow multiple configurations so it would work for tas-releng too.

Describe the solution you'd like

I'd like to see the build file name to be configurable in the Kilnfile. If the configuration does not exist, fall back to tile-"${TILE_VERSION}.pivotal.

Describe alternatives you've considered

No response

Additional context

This would require changes to the kiln-buildpack and the concourse resource to fetch tiles out of harbor.