Avoid invalid prop types warnings during development at user settings

Use the correct types for `deltaReportsVersion` and
`detailsExportFileName`.

src/web/pages/usersettings/usersettingspage.jsx

@@ -815,8 +815,8 @@ UserSettings.propTypes = {
   defaultSnmpCredential: PropTypes.object,
   defaultSshCredential: PropTypes.object,
   defaultTarget: PropTypes.object,
-  deltaReportsVersion: PropTypes.string,
-  detailsExportFileName: PropTypes.string,
+  deltaReportsVersion: PropTypes.numberOrNumberString,
+  detailsExportFileName: PropTypes.object,
   dfnCertFilter: PropTypes.object,
   dynamicSeverity: PropTypes.object,
   filters: PropTypes.array,