Test sharding

[VenelinMartinov]

This PR implements a test sharding strategy to speed up the bridge tests from 1 hour 30 minutes to under 15 minutes.

It uses https://github.com/VenelinMartinov/sharder which is a package for generating regexes to plug into go test based on the test profile data. The script is based on the previous work by @blampe in https://github.com/pulumi/shard.

This PR also adds two new make commands:

• make test_profile this regenerates the test profile data, so that shard partitioning can be more fair
• make test_shard. This is only run in CI. This command picks up the SHARD_CMD env var to determine which tests to run. SHARD_CMD is populated in CI by the sharder package and contains a regex which should match the correct tests to run.

Sharding is only done for ubuntu tests as they take the longest.

Example run: https://github.com/pulumi/pulumi-terraform-bridge/actions/runs/12656374664

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.62%. Comparing base (2c18440) to head (138e1d0).

Additional details and impacted files

@@                            Coverage Diff                             @@
##           vvm/refactor_sdkv2_detailed_diff_tests    #2810      +/-   ##
==========================================================================
- Coverage                                   68.63%   68.62%   -0.02%     
==========================================================================
  Files                                         325      325              
  Lines                                       41550    41550              
==========================================================================
- Hits                                        28518    28513       -5     
- Misses                                      11425    11430       +5     
  Partials                                     1607     1607              

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[VenelinMartinov]

This change is part of the following stack:

• move providerbuilder to pkg/pf/internal #2804
  • Add pb.Provider.ToProviderInfo test helper method #2805
    • Remove bridgedProvider test utilities in favour of ToProviderInfo #2812
      • Move PF detailed diff test to separate folder #2813
        • Refactor PF detailed diff tests #2814
          • Refactor sdkv2 detailed diff tests #2816
            • Test sharding #2810 ◀

_{Change managed by git-spice.}

[iwahbe]

This needs a comment explaining what it does.

[iwahbe]

This also needs a comment explaining what it does, and that it is provided for CI.

[iwahbe]

Why are we adding this. We should fix the test that erroneously generates this file instead of ignoring it.

[iwahbe]

Is the idea that every OS runs shard 0, and only ubuntu runs the rest of the shards? If so, that needs a comment explaining so.

Also, why don't we shard all OSs?

[iwahbe]

Instead of defining shard as [0, 1, 2, 3, ...], then excluding each option we don't want, can we define shard as [0] and then add explicit includes for other shard options. That will reduce the length of the shard list by half.

[iwahbe]

How is github.com/VenelinMartinov/sharder different from github.com/pulumi/shard? Why can't we use github.com/pulumi/shard?