fixed previous merge
[Stopwatch] Fix checking started events
merged branch Olden/issue_7639 (PR #7691)

This PR was squashed before being merged into the master branch (closes #7691).

Discussion
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[Stopwatch] Fix checking started events

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #7639, #7653
| License       | MIT

Stopwatch component return true from isStarted method, when StopwatchEvent was added but not started.

Commits
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b626542 [Stopwatch] Fix checking started events