feat(InvoiceError) - Improve create_for handling (#2770)

## description

If an invoice already has an invoice error, and still fails to generate.
We'd have a duplicate primary key violation.
we'd rather simply update the existing error object.

app/models/invoice_error.rb

@@ -4,12 +4,14 @@ class InvoiceError < ApplicationRecord
   # NOTE! Invoice errors will have the same id as the invoice they belong to.
   def self.create_for(invoice:, error:)
     return unless invoice
-
-    create(id: invoice.id,
+    instance = find_or_create_by(id: invoice.id)
+    instance.update(
       backtrace: error.backtrace,
       error: error.inspect.to_json,
       invoice: invoice.to_json(except: :file),
-      subscriptions: invoice.subscriptions.to_json)
+      subscriptions: invoice.subscriptions.to_json
+    )
+    instance
   end
 end
 

spec/models/invoice_error_spec.rb

@@ -38,5 +38,13 @@
       invoice_error = described_class.create_for(invoice:, error:)
       expect(invoice_error.subscriptions).to eq("[]")
     end
+
+    it "updates when create_for is called with the same invoice" do
+      invoice_error = described_class.create_for(invoice:, error:)
+      expect(invoice_error.id).to eq(invoice.id)
+
+      invoice_error = described_class.create_for(invoice:, error:)
+      expect(invoice_error.id).to eq(invoice.id)
+    end
   end
 end