fix(NA): unhandled exception for junit report generation when no code…

…owners (#187597)

This PR fixes what was brought on at
#181711 .

What was proposed won't work as we don't have codeowners files on
branches other than main.

(cherry picked from commit 228a6ff)

packages/kbn-test/src/mocha/junit_report_generation.js

@@ -94,7 +94,10 @@ export function setupJUnitReportGeneration(runner, options = {}) {
       .map((node) => ({ skipped: true, node }));
 
     // cache codeowners for quicker lookup
-    const reversedCodeowners = getPathsWithOwnersReversed();
+    let reversedCodeowners = [];
+    try {
+      reversedCodeowners = getPathsWithOwnersReversed();
+    } catch {}
 
     const commandLine = prettifyCommandLine(process.argv);