chore: fix calculation of overall duration during update-release-branch workflow

[ianbotsf]

Issue #

(none)

Description of changes

Well kat metrics emit is being now being invoked correctly but throws an error because duration isn't being stored properly. Example run:

Executing command "kat metrics emit --namespace "CI Metrics" --dimension "Product=aws-sdk-kotlin" --dimension "Trigger=manual" --metric "ReleaseMergeAttempted:1:Count" --metric "ReleaseMergeSucceeded:1:Count" --metric "ReleaseMergeCanceled:0:Count" --metric "ReleaseMergeFailed:0:Count" --metric "ReleaseMergeDuration::Seconds""
Usage: kat metrics emit [<options>]

Error: invalid value for --metric: Invalid numerical metric value ''

(Note that ReleaseMergeDuration::Seconds contains no value)

Hopefully this is the final fix!

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[sonarqubecloud]

Quality Gate passed

Issues
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0 Accepted issues

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0.0% Duplication on New Code

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