Remove redundant 'Apply workflow_dispatch overrides' step from build workflows

[simonrosenberg]

Summary

This PR removes the redundant "Apply workflow_dispatch overrides" step from build workflows by replacing hardcoded env defaults with ${{ inputs.X || 'default' }} expressions.

Fixes #565

Changes

Pattern Applied

Before:

env:
  DATASET: 'princeton-nlp/SWE-bench_Verified'
# ...
steps:
  - name: Apply workflow_dispatch overrides (if any)
    if: ${{ github.event_name == 'workflow_dispatch' }}
    run: |
      if [ -n "${{ inputs.dataset }}" ]; then echo "DATASET=${{ inputs.dataset }}" >> "$GITHUB_ENV"; fi

After:

env:
  DATASET: ${{ inputs.dataset || 'princeton-nlp/SWE-bench_Verified' }}

This works because:

• For workflow_dispatch: the input value is used directly
• For pull_request_target: inputs are empty so the || fallback applies

Workflows Updated

• .github/workflows/build-swebench-images.yml
• .github/workflows/build-commit0-images.yml
• .github/workflows/build-multiswebench-images.yml
• .github/workflows/build-swebenchmultimodal-images.yml
• .github/workflows/build-swegym-images.yml
• .github/workflows/build-swesmith-images.yml

Additional Cleanup

Also removes unused env vars that were defined but never referenced:

• BUILD_BATCH_SIZE
• BUILDKIT_PRUNE_KEEP_GB
• BUILDKIT_PRUNE_THRESHOLD_PCT

These were present in build-multiswebench-images.yml, build-swegym-images.yml, and build-swesmith-images.yml.

Testing

This is a workflow configuration change. The behavior should be equivalent for both trigger types:

• Workflow dispatch will use input values with fallback defaults
• PR trigger will use fallback defaults (since inputs are empty), then the "Set N_LIMIT based on label" step will override for PR-specific behavior

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This PR was created by an AI assistant (OpenHands) on behalf of the user.

@simonrosenberg can click here to continue refining the PR