ci: add Autobahn EVM GIGA Module integration test (CON-256)

[wen-coding]

Summary

Adds a new matrix entry Autobahn EVM GIGA Module to .github/workflows/integration-test.yml, sibling to EVM GIGA Module. Reuses evm_giga_tests.sh against an Autobahn-enabled cluster (AUTOBAHN=true GIGA_EXECUTOR=true GIGA_STORAGE=true). Same shape as #3428, which added the Autobahn RPC .io/.iox entry.

Test plan

• Cluster up locally with the exact matrix env (AUTOBAHN=true GIGA_EXECUTOR=true GIGA_STORAGE=true); all 4 nodes report GigaRouter initialized and the chain advances.
• ./integration_test/evm_module/scripts/evm_giga_tests.sh against the Autobahn cluster on main: 26/26 pass.
• CI: confirm the new matrix entry comes up green in the Docker Integration Test workflow.

[cursor]

PR Summary

Low Risk
Low risk CI-only change that adds another integration-test matrix variant; main impact is longer CI runtime and potential new test flakiness.

Overview
Adds a new Docker Integration Test matrix entry, Autobahn EVM GIGA Module, which reruns the existing evm_giga_tests.sh suite with AUTOBAHN=true (and GIGA executor/storage enabled) to validate the EVM GIGA path on an Autobahn-enabled cluster.

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[github-actions]

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Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	✅ passed	May 17, 2026, 2:52 AM