Update VisionCameraTextRecognitionPlugin.kt

[CECSMH]

just correction of mismatch hashmap type, to solve follow issue found at newer API versions.

> Task :react-native-vision-camera-text-recognition:compileDebugKotlin FAILED
e: file:///C:/Labs/Mobile/auto_max/node_modules/react-native-vision-camera-text-recognition/android/src/main/java/com/visioncameratextrecognition/VisionCameraTextRecognitionPlugin.kt:54:24 Return type mismatch: expected 'java.util.HashMap<kotlin.String, kotlin.Any>?', actual 'java.util.HashMap<kotlin.String, kotlin.Any?>'.
e: file:///C:/Labs/Mobile/auto_max/node_modules/react-native-vision-camera-text-recognition/android/src/main/java/com/visioncameratextrecognition/VisionCameraTextRecognitionPlugin.kt:58:20 Return type mismatch: expected 'java.util.HashMap<kotlin.String, kotlin.Any>?', actual 'java.util.HashMap<kotlin.String, kotlin.Any?>'.

[gmattinson]

This PR fixes #34

[Legonois]

looks good? need this fixed asap lol