Stable sort of execution logs is unaware of shards

Description of the problem / feature request:

If I use

--execution_log_json_file

or

--experimental_execution_log_file

and then use the ./bazel-bin/src/tools/execlog/parser to sort two exec logs together from different machines, the outputs will put shards in random orders.

For example:

      "path": "bazel-out/k8-fastbuild/testlogs/brokeback/brokeback_test/shard_24_of_36/test.xml",
      "digest": {
        "hash": "0d030e2e27dd936a8bb63b868af28b0b7ae307100cf6b29928838315a1a3781f",

appears after

      "path": "bazel-out/k8-fastbuild/testlogs/brokeback/brokeback_test/shard_23_of_36/test.xml",

in one file but after

      "path": "bazel-out/k8-fastbuild/testlogs/brokeback/brokeback_test/shard_25_of_36/test.xml",

in another

Feature requests: what underlying problem are you trying to solve with this feature?

Please sort shards stabably

Bugs: what's the simplest, easiest way to reproduce this bug? Please provide a minimal example if possible.

Make a build with 2 shards, have them finish in different orders on different machines and see that the execlog isn't consistent between the two

What operating system are you running Bazel on?

Linux

What's the output of bazel info release?

release 6.0.0-pre.20220310.1

If bazel info release returns "development version" or "(@non-git)", tell us how you built Bazel.

Replace this line with your answer.

What's the output of git remote get-url origin ; git rev-parse master ; git rev-parse HEAD ?

Internal Company repo

Have you found anything relevant by searching the web?

No

Any other information, logs, or outputs that you want to share?

Replace this line with your answer.