await TimelineSummary.write***ToFile

[CareF]

Description

TimelineSummary.writeSummaryToFile and TimelineSummary.writeTimelineToFile are async IO method, but in many of our use cases they are not awaited, but rely on zone to await when exit. This PR await them explicitly.

In the unit test case of TimelineSummary they are awaited, so this most likely happened when we switched from sync IO to async IO.

Related Issues

N/A

Tests

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Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I signed the CLA.
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• I updated/added relevant documentation (doc comments with ///).
• All existing and new tests are passing.
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Breaking Change

Did any tests fail when you ran them? Please read Handling breaking changes.

• No, no existing tests failed, so this is not a breaking change.