fix: Correct dead fallback for service name

Since `respond_to?(:name)` returns always `true`.

Author: blocknotes

lib/active_storage/service/db_service.rb

@@ -111,7 +111,7 @@ def headers_for_direct_upload(_key, content_type:, **)
     private
 
     def service_name_for_token
-      respond_to?(:name) ? name : "db"
+      name.presence || "db"
     end
 
     def adapter_sqlite?

spec/service/active_storage/service/db_service_spec.rb

@@ -317,6 +317,18 @@
     end
   end
 
+  describe "service_name_for_token" do
+    it "returns the service name when set" do
+      service.name = "custom_db"
+      expect(service.send(:service_name_for_token)).to eq("custom_db")
+    end
+
+    it "falls back to 'db' when name is nil" do
+      service.name = nil
+      expect(service.send(:service_name_for_token)).to eq("db")
+    end
+  end
+
   describe "chunk_size validation" do
     it "enforces a minimum chunk size of 1" do
       allow(ENV).to receive(:fetch).with("ASDB_CHUNK_SIZE").and_return("0")