Generate a metadata file artifact in unit test buildkite job

[taylanisikdemir]

What changed?
unit test job in buildkite pipelines will generate a new file as an artifact.

Why?
This is needed to integrate with SonarQube.

How did you test it?
Run ./scripts/buildkite/gen_coverage_metadata.sh .build/coverage/metadata.txt and check the content of metadata.txt.

commit-sha: 089095d18943cfc58bde19a1436876d97ec5559f
timestamp: 2024-03-04T19:35:21Z

Also checked the buildkite job that runs as part of the PR:

[coveralls]

Pull Request Test Coverage Report for Build 018e0b41-63d7-4de9-ba4d-75334ec09400

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 81 unchanged lines in 10 files lost coverage.
• Overall coverage decreased (-0.001%) to 62.924%

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Files with Coverage Reduction	New Missed Lines	%
common/peerprovider/ringpopprovider/config.go	2	81.58%
common/task/parallel_task_processor.go	2	93.06%
common/task/weighted_round_robin_task_scheduler.go	2	88.56%
service/matching/taskListManager.go	2	79.7%
common/persistence/nosql/nosqlplugin/cassandra/workflow.go	3	61.45%
common/persistence/statsComputer.go	3	94.64%
common/task/fifo_task_scheduler.go	7	82.47%
common/persistence/sql/workflowStateMaps.go	11	83.84%
common/persistence/nosql/nosqlplugin/cassandra/workflow_parsing_utils.go	20	79.13%
service/history/execution/mutable_state_task_refresher.go	29	57.59%

Totals
Change from base Build 018e0b2e-f9ef-4696-ae22-4d312de4faa2:	-0.001%
Covered Lines:	93010
Relevant Lines:	147813

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💛 - Coveralls