fix: reducer removes guestCartId when it fails

[zetlen]

This PR is a:

[ ] New feature
[ ] Enhancement/Optimization
[ ] Refactor
[x] Bugfix
[ ] Test for existing code
[ ] Documentation

Summary

When this pull request is merged, it will fix an issue where a stale guestCartId in local storage will cause an infinite loop, as the app repeatedly attempts to load an expired cart and tries again when it fails.

Fixed this by making sure that the reducer deletes a known-bad guest cart ID.

Additional information

[PWAStudioBot]

	Fails
🚫	The following file(s) did not pass ESLint. Execute npm run lint locally for more details packages/venia-concept/src/actions/cart/__tests__/asyncActions.spec.js

Generated by 🚫 dangerJS

[coveralls]

Pull Request Test Coverage Report for Build 1056

• 11 of 11 (100.0%) changed or added relevant lines in 2 files are covered.
• 536 unchanged lines in 21 files lost coverage.
• Overall coverage decreased (-15.1%) to 15.937%

---

Files with Coverage Reduction	New Missed Lines	%
packages/pwa-buildpack/src/WebpackTools/index.js	1	0.0%
packages/pwa-buildpack/src/util/promisified/openport.js	3	0.0%
packages/pwa-buildpack/src/util/promisified/child_process.js	3	0.0%
packages/pwa-buildpack/src/util/promisified/dns.js	3	0.0%
packages/pwa-buildpack/src/util/promisified/fs.js	3	0.0%
packages/pwa-buildpack/src/WebpackTools/MagentoResolver.js	5	0.0%
packages/pwa-buildpack/src/WebpackTools/middlewares/StaticRootRoute.js	7	0.0%
packages/pwa-buildpack/src/magento-layout-loader/validateConfig.js	13	0.0%
packages/pwa-buildpack/src/WebpackTools/plugins/DevServerReadyNotifierPlugin.js	13	0.0%
packages/pwa-buildpack/src/WebpackTools/plugins/ServiceWorkerPlugin.js	16	0.0%

Totals
Change from base Build 1047:	-15.1%
Covered Lines:	258
Relevant Lines:	1733

---

💛 - Coveralls

[jimbo]

Looks good to me. Some of these tests are pretty gross—inline snapshots are particularly bad. But happy path works and I'm not able to reproduce the bug.