fix: add human-readable name for DonationSite model to en.yml

Author: hagiya0121

config/locales/en.yml

@@ -39,4 +39,5 @@ en:
       distribution:
         issued_at: "Distribution date and time"
     models:
-      product_drive: "Product Drive"
+      product_drive: "Product Drive"
+      donation_site: "Donation Site"

spec/system/donation_system_spec.rb

@@ -362,7 +362,7 @@
 
         it "Allows User to create a Donataion Site from donation" do
           select Donation::SOURCES[:donation_site], from: "donation_source"
-          select "---Create New Donation site---", from: "donation_donation_site_id"
+          select "---Create New Donation Site---", from: "donation_donation_site_id"
 
           find(".modal-content")
           expect(page).to have_content("New Donation Site")