Ignore missing PDF errors in Sentry error reporting (#6529)

GitOrigin-RevId: fc61a2499ec3e8ff95a7058aea65b9d41ed8bd62

services/web/frontend/js/infrastructure/error-reporter.js

@@ -26,6 +26,7 @@ function sentryReporter() {
             'SecurityError: Permission denied to access property "pathname" on cross-origin object',
             // Ignore unhandled error that is "expected" - see https://github.com/overleaf/issues/issues/3321
             /^Missing PDF/,
+            /^pdfng error Error: MissingPDFException/,
             // Ignore "expected" error from aborted fetch - see https://github.com/overleaf/issues/issues/3321
             /^AbortError/,
             // Ignore spurious error from Ace internals - see https://github.com/overleaf/issues/issues/3321