Update to feature_extractor_type and reduce_labels due to deprecation notices.

preprocessor_config.json

@@ -1,7 +1,7 @@
 {
   "do_normalize": true,
   "do_resize": true,
-  "feature_extractor_type": "SegformerFeatureExtractor",
+  "image_processor_type": "SegformerImageProcessor",
   "image_mean": [
     0.485,
     0.456,
@@ -12,7 +12,7 @@
     0.224,
     0.225
   ],
-  "reduce_labels": false,
+  "do_reduce_labels": false,
   "resample": 2,
   "size": 1024
 }