fix: Make artifact bundle creation deterministic

[loewenheim]

Building an artifact bundle is currently nondeterministic. This is because of two factors:

1. We depend on an outdated version of symbolic in which the order in which you add files to a source bundle matters.
2. When building the bundle, we iterate over source files in nondeterministic order.

This adds a failing test and then fixes the problem by updating symbolic and presorting source files.

[Swatinem]

Well the add_file API is still order dependent thats why you have to sort.

It used to use a default timestamp which was obviously not deterministic, but now we are just writing files with a deterministic timestamp. Looks like I never pushed that fix / update to symbolic. I remember I did try it locally for sure.

[loewenheim]

Well the add_file API is still order dependent thats why you have to sort.

It used to use a default timestamp which was obviously not deterministic, but now we are just writing files with a deterministic timestamp. Looks like I never pushed that fix / update to symbolic. I remember I did try it locally for sure.

Should we fix that in symbolic before merging this or just leave it like it is?

[Swatinem]

Well you also don’t want to buffer everything in RAM before you write it out to file… I guess that is one of the main reasons that add_file does not internally buffer/sort.