Make the value entering of the billing state field in e2e test compatible with WC < 9.2

[eason9487]

Changes proposed in this Pull Request:

This PR applies the same adjustment in woocommerce/woocommerce-google-analytics-integration#457 to make e2e test compatible with WC < 9.2.

Detailed test instructions:

1. npm run wp-env:up
2. npm run -- wp-env run tests-cli -- wp plugin update woocommerce --version=9.1.4 && npm run -- wp-env run tests-cli -- wp wc update
3. npm run test:e2e
4. Confirm tests pass
5. npm run -- wp-env run tests-cli -- wp plugin update woocommerce --version=9.2.0-rc.1 && npm run -- wp-env run tests-cli -- wp wc update
6. npm run test:e2e
7. Confirm tests pass

Changelog entry

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.8%. Comparing base (fe41b5b) to head (a4d6d00).
Report is 2 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff              @@
##             develop   #2528      +/-   ##
============================================
- Coverage       64.7%   63.8%    -0.9%     
============================================
  Files            801     326     -475     
  Lines          22976    5086   -17890     
  Branches        1229    1229              
============================================
- Hits           14875    3247   -11628     
+ Misses          7934    1672    -6262     
  Partials         167     167              

Flag	Coverage Δ
js-unit-tests	63.8% <ø> (ø)
php-unit-tests	?

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see 475 files with indirect coverage changes

[eason9487]

Ran e2e test with WooCommerce 9.1.4 and 9.2.0-rc.1 via GitHub actions:

• 9.1.4: https://github.com/woocommerce/google-listings-and-ads/actions/runs/10402153354/job/28806079914
• 9.2.0-rc.1: https://github.com/woocommerce/google-listings-and-ads/actions/runs/10402355426/job/28807223198

I will be merging this PR without code reviews.