fix: add sourceLocale: en (#1738)

* fix: add sourceLocale: en

* Fix code style issues with ESLint
Co-authored-by: Lint Action <lint-action@samuelmeuli.com>

lingui.config.js

@@ -18,4 +18,5 @@ module.exports = {
   pseudoLocale: 'pseudo-en',
   rootDir: '.',
   runtimeConfigModule: ['@lingui/core', 'i18n'],
+  sourceLocale: 'en',
 }