fix: make gateway deploy workflow parseable

[Pigbibi]

Summary

• fix the malformed multi-line Python snippet that made .github/workflows/main.yml fail before jobs were created
• stop workflow-only edits from triggering the gateway deploy workflow on push
• update the workflow shared-config test to match that safer trigger behavior

Validation

• actionlint .github/workflows/main.yml
• bash tests/test_install_2fa_bot_watcher.sh
• bash tests/test_wait_for_ib_gateway_ready.sh
• bash tests/test_workflow_shared_config.sh
• bash tests/test_docker_compose_ports.sh
• bash tests/test_gateway_recovery_scripts.sh
• git diff --check