Deleting last test case result throw an error

[TeddyCr]

Affected module
Backend

Describe the bug
When deleting the last test case result when trying to update the test suite summary status will throw an error - ln 333 TestCaseRepository.java

        ResultSummary newResultSummary =
            getResultSummary(
                testCase, testCaseResult.getTimestamp(), testCaseResult.getTestCaseStatus());
        resultSummaries.add(newResultSummary);
      }

To Reproduce
Add 1 test case result, delete it. You should see

{
    "responseMessage": "An exception with message [Cannot invoke \"org.openmetadata.schema.tests.type.TestCaseResult.getTimestamp()\" because \"testCaseResult\" is null] was thrown while processing request."
}

Expected behavior
Summary should be set to null for the testSuite

Version:

• OpenMetadata version: 1.2.x