erp5_test_result: fix getIntIndex attribute error for Scalability Test

Suite

Module erp5.component.document.erp5_version.ERP5ProjectUnitTestDistributor, line 326, in getTestSuiteSortKey
  wanted_test_core_quantity = PRIORITY_MAPPING[test_suite.getIntIndex()][1]
AttributeError: getIntIndex
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01:34:26

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01:38:15

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00:16:04

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00:21:27

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00:09:27

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