Fix container matching to handle sha256: prefix in image IDs

The container Image and ImageID fields contain full SHA256 hashes with
'sha256:' prefix, while @image.id is the short 12-character ID. Changed
from exact equality checks to substring matching using include?().

Author: chorrell

spec/spec_helper.rb

@@ -15,21 +15,14 @@ def create_image(version)
 
   def delete_image
     puts "Deleting image..."
-    puts "Image ID to delete: #{@image.id}"
-    
     # Stop and remove only containers created from this image
     Docker::Container.all(:all => true).each do |container|
       container_image = container.info['Image']
       container_image_id = container.info['ImageID']
 
-      puts "Container #{container.id[0..11]}: Image=#{container_image}, ImageID=#{container_image_id}"
-      
-      # Match both short and long image IDs
-      if container_image == @image.id || 
-         container_image == @image.id[0..11] || 
-         container_image_id == @image.id ||
-         container_image_id == @image.id[0..11]
-        puts "  -> Matches! Removing container #{container.id[0..11]}"
+      # Match image IDs - container IDs may have sha256: prefix and be full hashes
+      # while @image.id is the short ID
+      if container_image&.include?(@image.id) || container_image_id&.include?(@image.id)
         begin
           container.stop unless container.info['State'] == 'exited'
           container.delete(:force => true)