Fix typo in GenerationConfig.kt (#6250)

s/MINE/MIME/g

Author: rlazo

firebase-vertexai/src/main/kotlin/com/google/firebase/vertexai/type/GenerationConfig.kt

@@ -30,7 +30,7 @@ package com.google.firebase.vertexai.type
  * [Vertex AI documentation](https://cloud.google.com/vertex-ai/docs/reference/rest/v1beta1/GenerationConfig#FIELDS.response_mime_type)
  * for a list of supported types.
  * @property responseSchema A schema that the response must adhere to, used with the
- * `application/json` MINE type.
+ * `application/json` MIME type.
  */
 class GenerationConfig
 private constructor(