docs: fix `app.getPreferredSystemLanguages()` return type (#37837)

docs: fix app.getPreferredSystemLanguages() return type

Co-authored-by: trop[bot] <37223003+trop[bot]@users.noreply.github.com>
Co-authored-by: Shelley Vohr <[email protected]>

docs/api/app.md

@@ -751,14 +751,21 @@ This API can be used for purposes such as deciding what language to present the
 
 Here are some examples of return values of the various language and locale APIs with different configurations:
 
-* For Windows, where the application locale is German, the regional format is Finnish (Finland), and the preferred system languages from most to least preferred are French (Canada), English (US), Simplified Chinese (China), Finnish, and Spanish (Latin America):
-  * `app.getLocale()` returns `'de'`
-  * `app.getSystemLocale()` returns `'fi-FI'`
-  * `app.getPreferredSystemLanguages()` returns `['fr-CA', 'en-US', 'zh-Hans-CN', 'fi', 'es-419']`
-* On macOS, where the application locale is German, the region is Finland, and the preferred system languages from most to least preferred are French (Canada), English (US), Simplified Chinese, and Spanish (Latin America):
-  * `app.getLocale()` returns `'de'`
-  * `app.getSystemLocale()` returns `'fr-FI'`
-  * `app.getPreferredSystemLanguages()` returns `['fr-CA', 'en-US', 'zh-Hans-FI', 'es-419']`
+On Windows, given application locale is German, the regional format is Finnish (Finland), and the preferred system languages from most to least preferred are French (Canada), English (US), Simplified Chinese (China), Finnish, and Spanish (Latin America):
+
+```js
+app.getLocale() // 'de'
+app.getSystemLocale() // 'fi-FI'
+app.getPreferredSystemLanguages() // ['fr-CA', 'en-US', 'zh-Hans-CN', 'fi', 'es-419']
+```
+
+On macOS, given the application locale is German, the region is Finland, and the preferred system languages from most to least preferred are French (Canada), English (US), Simplified Chinese, and Spanish (Latin America):
+
+```js
+app.getLocale() // 'de'
+app.getSystemLocale() // 'fr-FI'
+app.getPreferredSystemLanguages() // ['fr-CA', 'en-US', 'zh-Hans-FI', 'es-419']
+```
 
 Both the available languages and regions and the possible return values differ between the two operating systems.