Make the fake IPA size a constant

Author: AliSoftware

spec/ios_send_app_size_metrics_spec.rb

@@ -4,6 +4,7 @@
   let(:test_data_dir) { File.join(File.dirname(__FILE__), 'test-data', 'app_size_metrics') }
   let(:mocked_endpoint) { 'https://localhost/api/metrics' }
   let(:mocked_token) { 'token/1' }
+  let(:fake_ipa_size) { 1337 } # The value used in the `app-thinning.plist` and `app-size-metrics-payload.json` fixtures
 
   # Utility method to turn a minified JSON into a pretty-formatted JSON (without the GZIP fake prefix if any)
   # To make any test failure and diff easier to debug
@@ -78,7 +79,7 @@ def test_app_size_action(fake_ipa_size:, expected_json:, **other_action_args)
     expected_json = JSON.parse(File.read(expected_fixture)).to_json
 
     test_app_size_action(
-      fake_ipa_size: 1337,
+      fake_ipa_size: fake_ipa_size,
       expected_json: expected_json,
       app_thinning_plist_path: app_thinning_plist_path,
       app_name: 'wordpress',