List only failed tests

Fixes issue #142

src/report/get-report.ts

@@ -263,6 +263,9 @@ function getTestsReport(ts: TestSuiteResult, runIndex: number, suiteIndex: numbe
     }
     const space = grp.name ? '  ' : ''
     for (const tc of grp.tests) {
+      if (options.listTests === 'failed' && tc.result !== 'failed') {
+        continue
+      }
       const result = getResultIcon(tc.result)
       sections.push(`${space}${result} ${tc.name}`)
       if (tc.error) {