Description

The generateFuzzerBasedSummariesForTests method returned an empty clustersToReturn when methodDescriptionSource == SYMBOLIC. And all symbolic tests were lost when at least one fuzzer test was generated.

Self-check list

• I've set the proper labels for my PR (at least, for category and component).
• PR title and description are clear and intelligible.
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• The functionality I've repaired, changed or added is covered with automated tests.
• Manual tests have been provided optionally.
• The documentation for the functionality I've been working on is up-to-date.