Restore alt text to Practice main display image (#991)

Co-authored-by: Camille Villa <[email protected]>

app/models/practice.rb

@@ -28,7 +28,7 @@ class Practice < ApplicationRecord
   attr_accessor :delete_main_display_image
   attr_accessor :crop_x, :crop_y, :crop_w, :crop_h
   attr_accessor :practice_partner, :department, :practice_award, :category
-  attr_accessor :main_display_image_alt_text, :highlight_attachment_content_type
+  attr_accessor :highlight_attachment_content_type
 
   def self.cached_json_practices(is_guest_user)
     if is_guest_user
@@ -433,8 +433,7 @@ def diffusion_history_status_by_facility(facility)
   def trim_whitespace
     strip_attributes(
       [
-        self.name,
-        self.main_display_image_alt_text
+        self.name
       ]
     )
   end