Always print test_execution_id

[cgchinmay]

Description

[Describe what this change achieves]

display test execution id before running test for start and execution-test commands. These are the only 2 subcommands which use this argument.

Issues Resolved

[List any issues this PR will resolve]
#471

Testing

• New functionality includes testing

[Describe how this change was tested]
Ran without custom test execution id

python3 osbenchmark/benchmark.py execute-test --pipeline=benchmark-only --workload=percolator --target-host=https://localhost:9200/ --client-options=basic_auth_user:admin,basic_auth_password:admin,verify_certs:false --test-mode                                     

[INFO] [Test Execution ID]: a7b0f002-573c-41c6-a2fb-8df7d9ad0ff6
[INFO] You did not provide an explicit timeout in the client options. Assuming default of 10 seconds.
[INFO] Executing test with workload [percolator], test_procedure [append-no-conflicts] and provision_config_instance ['external'] with version [2.12.0]

With custom id

python3 osbenchmark/benchmark.py execute-test --pipeline=benchmark-only --workload=percolator --target-host=https://localhost:9200/ --client-options=basic_auth_user:admin,basic_auth_password:admin,verify_certs:false --test-mode --test-execution-id "custom-test-123"

[INFO] [Test Execution ID]: custom-test-123

Validated make test

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[beaioun]

LGTM