NOISSUE - Improve reliability of state machine test

[SammyOina]

What type of PR is this?

What does this do?

• Bug Fixes

  • Improved test reliability by adding delays in state machine transition tests to ensure asynchronous operations complete before assertions.

• Chores

  • Updated service identifier for clarity, changing svcName from "manager_test_server" to "computations_test_server".
  • Added a new target for test coverage in the Makefile, enhancing test reporting capabilities.

• Documentation

  • Introduced a coverage badge in the README.md to visually indicate the project's test coverage status.

Which issue(s) does this PR fix/relate to?

Have you included tests for your changes?

Did you document any new/modified feature?

Notes

[dborovcanin]

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