Fix text line mappings

Author: robmoorman

Diff for: wagtailstreamforms/wagtailstreamforms_fields.py

@@ -180,8 +180,8 @@ def get_form_block(self):
 
 
 FIELD_MAPPING = {
-    "singleline": SingleFileField,
-    "multiline": MultiFileField,
+    "singleline": SingleLineTextField,
+    "multiline": MultiLineTextField,
     "date": DateField,
     "datetime": DateTimeField,
     "email": EmailField,