Run benchmarking in dedicated agents (application and load)

[kshyju]

With this change, the application and load generators run on separate agents. To share the application agent's IP address with the load generator agent, we use Azure Table Storage. Job output variables are not suitable as they become available only after the job finishes, whereas we need the job (agent) to remain running.

Sample pipeline run:

1. https://azfunc.visualstudio.com/internal/_build/results?buildId=199693&view=results

IMPORTANT: Currently, changes must be backported to the in-proc branch to be included in Core Tools and non-Flex deployments.

• Backporting to the in-proc branch is not required
  • Otherwise: Link to backporting PR
• My changes do not require documentation changes
  • Otherwise: Documentation issue linked to PR
• My changes should not be added to the release notes for the next release
  • Otherwise: I've added my notes to release_notes.md
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• My changes do not require diagnostic events changes
  • Otherwise: I have added/updated all related diagnostic events and their documentation (Documentation issue linked to PR)
• I have added all required tests (Unit tests, E2E tests)