Upgrade eslint to v8.x

[davidjoy]

We're currently using eslint v6.x. We'd like to upgrade this to the latest stable release v8.x.

We should be able to do this without creating any new linting errors, hopefully.

Also, it's worth noting that automated updates in https://github.com/edx/eslint-config updated our version of eslint there to 7.x. These dependencies are only used in development of the eslint-config, as it declares them as peer dependencies. https://github.com/edx/frontend-build defines the actual eslint dependencies we use, which use v6.x. So, despite our config being on v7, everything else is still on v6.x and (luckily) nothing has broken. We should straighten out this situation when doing this upgrade.

PRs

Base

• Upgrade eslint to v8.x  frontend-build#252
• Updated front-build to v12 frontend-platform#354
• Upgrade eslint to v8.x paragon#1421
• Updated frontend-build to v12 frontend-template-application#472

Components

• Upgrade frontend-build to v12  frontend-component-header#249
• frontend-build updated to v12 edx/frontend-component-header-edx#277
• Upgrade frontend-build to v12 frontend-component-footer#228
• Update frontend-build to v12 edx/frontend-component-footer-edx#196
• Eslint upgrade frontend-component-cookie-policy-banner#403

MFEs

• refactor: upgraded frontend-build version to v12 frontend-app-gradebook#254
• refactor: upgraded frontend-build version to v12 frontend-app-publisher#757
• chore: upgrade frontend-build and paragon to latest frontend-app-admin-portal#901
• Upgraded frontend-build version to v12 frontend-app-profile#589
• refactor: upgraded frontend-build version to v12 openedx-unsupported/frontend-app-ecommerce#204
• Upgraded frontend-build version to v12 frontend-app-account#613
• refactor: upgraded frontend-build version to v12 frontend-app-authoring#322
• Upgraded frontend-build version to v12 openedx-unsupported/frontend-app-library-authoring#51
• Upgraded frontend-build to v12 frontend-app-learner-record#72
• Updated frontend-build to v12 frontend-app-communications#66
• Updated frontend-build to v12 frontend-app-learning#962
• refactor: updated frontend-build to v12 & resolved eslint issues openedx-unsupported/frontend-app-payment#620
• Upgrade eslint to v8.x frontend-app-learner-portal-programs#249
• refactor: updated frontend-build & resolved eslint issues frontend-app-profile#654

Enterprise

• Updated frontend-build to v12 frontend-enterprise#270
• Updated frontend-build to v12 frontend-app-enterprise-public-catalog#244
• refactor: updated frontend-build & resolved eslint issues frontend-app-enterprise-public-catalog#265
• Upgraded frontend-build version frontend-app-learner-portal-enterprise#593

[arbrandes]

@BilalQamar95, sprint check: we're just waiting for reviews/merges, correct?

[BilalQamar95]

@arbrandes Yes, these are waiting for reviews/merges

[arbrandes]

@BilalQamar95, are we done here?

[BilalQamar95]

@BilalQamar95, are we done here?

Yes, seems concluded.