Update language-support.md

Author: DishaAgarwal

articles/cognitive-services/language-service/language-detection/language-support.md

@@ -160,6 +160,7 @@ If you have content expressed in a less frequently used language, you can try La
 | Hindi               | `hi`          | 2022-10-01                   |
 | Kannada             | `kn`          | 2022-10-01                   |
 | Malayalam           | `ml`          | 2022-10-01                   |
+| Marathi             | `mr`          | 2022-10-01                   |
 | Oriya               | `or`          | 2022-10-01                   |
 | Punjabi             | `pa`          | 2022-10-01                   |
 | Tamil               | `ta`          | 2022-10-01                   |