fix(desktop-gui): remember last browser used w/ non-default channel

[flotwig]

• Closes Last-used browser is incorrectly remembered in desktop-gui #8281

User facing changelog

• Fixed a bug where the "last used browser" would be incorrectly remembered in cypress open if a non-default-channel browser was selected.

Additional details

How has the user experience changed?

PR Tasks

• Have tests been added/updated?
• Has the original issue been tagged with a release in ZenHub?
• [na] Has a PR for user-facing changes been opened in cypress-documentation?
• [na] Have API changes been updated in the type definitions?
• [na] Have new configuration options been added to the cypress.schema.json?

[cypress-bot]

Thanks for taking the time to open a PR!

• Create a Draft Pull Request if your PR is not ready for review. Mark the PR as Ready for Review when you're ready for a Cypress team member to review the PR.
• Become familiar with the Code Review Checklist for guidelines on coding standards and what needs to be done before a PR can be merged.

[cypress]

---

Test summary

8118 • 0 • 108 • 3

---

Run details

Project	cypress
Status	Passed
Commit	ee60b01
Started	Aug 14, 2020 7:36 PM
Ended	Aug 14, 2020 7:42 PM
Duration	05:45 💡
OS	Linux Debian - 10.2
Browser	Multiple

View run in Cypress Dashboard ➡️

---

This comment has been generated by cypress-bot as a result of this project's GitHub integration settings. You can manage this integration in this project's settings in the Cypress Dashboard

[bahmutov]

can we clearly have 3 tests here:

• nothing is in localStorage under choseBrowser
• old way chromium
• new way with stringified object

[bahmutov]

I think this is good, I just want clear tests for different situations to ensure the code is covered

[bahmutov]

looks good