feat: add tpu_vm_create_topology/startup_script

[gryczj]

Description

Fixes #<ISSUE-NUMBER>

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Checklist

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[snippet-bot[bot]]

Here is the summary of changes.

You are about to add 2 region tags.

• tpu/createStartupScriptVM.js:20, tag tpu_vm_create_startup_script
• tpu/createTopologyVM.js:20, tag tpu_vm_create_topology

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[gryczj]

Due to high costs of TPU Nodes, it was decided to use mocks in the tests.