test: split long sim test into 3 parts

[egonspace]

Description

Github action job execution time - Each job in a workflow can run for up to 6 hours of execution time. If a job reaches this limit, the job is terminated and fails to complete. from https://docs.github.com/en/actions/learn-github-actions/usage-limits-billing-and-administration.

Existing test-sim-multi-seed-long test takes over 6 hours, so it failed because of github action timeout.
So I split this test into 3 parts.

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• Targeted PR against correct branch (see CONTRIBUTING.md)
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the module structure standards.
• Wrote unit and integration tests
• Updated relevant documentation (docs/) or specification (x/<module>/spec/)
• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• Re-reviewed Files changed in the Github PR explorer
• Review Codecov Report in the comment section below once CI passes

[dudong2]

LGTM

[0Tech]

LGTM

[whylee259]

LGTM