Ignore jquery migrate console warnings when running e2e tests

[isabel_brison]

When running e2e tests, console warnings generated by the jquery migrate script are output, creating a lot of noise that makes browsing the test results unnecessarily painful. E.g. this is output several times per test:

console.warn
    JQMIGRATE: jQuery.isFunction() is deprecated

      113 |
      114 | 		// eslint-disable-next-line no-console
    > 115 | 		console[ logFunction ]( text );
          | 		^
      116 | 	} );
      117 | }
      118 |

      at config/bootstrap.js:115:3
      at ../../node_modules/puppeteer/lib/cjs/vendor/mitt/src/index.js:51:62
          at Array.map (<anonymous>)
      at Object.emit (../../node_modules/puppeteer/lib/cjs/vendor/mitt/src/index.js:51:43)
      at Page.emit (../../node_modules/puppeteer/lib/cjs/puppeteer/common/EventEmitter.js:72:22)
      at Page._addConsoleMessage (../../node_modules/puppeteer/lib/cjs/puppeteer/common/Page.js:757:14)
      at Page._onConsoleAPI (../../node_modules/puppeteer/lib/cjs/puppeteer/common/Page.js:700:14)

We should add something in the e2e setup to ignore these warnings.

Trac ticket: https://core.trac.wordpress.org/ticket/52860

[desrosj]

@isabel_brison are these errors being triggered by code within the devDependencies? Or within Core code? If the former, would ignoring these warnings result in deprecated patterns in Core code being missed? I know that jQuery Migrate is slated to be removed from Core eventually, but it's still included for the time being.

The 5.8 cutoff is today, but test improvements are allowed at any time, so this can stay for the time being.

[isabel_brison]

There's a couple uses of $.isFunction() in Twenty Seventeen, and the rest of the warnings are coming from jQuery UI. The warnings also appear in the browser console when running a dev environment though, so we won't miss them if we remove them from the e2e tests. And the benefit of removing them is the test results become much more readable, as all the warnings are currently being output after each test.

[desrosj]

Thanks for clarifying! I say let's get this in then.

[desrosj]

In 51130:

Build/Test Tools: Silence jQuery Migrate console warnings when running E2E tests.

These warnings will still be visible in the browser console. The majority of the warnings are coming from jQuery UI, which is still waiting for a new update to be released that is jQuery >= 3.0 friendly.

This change makes the E2E test results more readable without having to tread through the large number of warnings.

Props isabel_brison.
Fixes #52860.

Committed via changeset https://core.trac.wordpress.org/changeset/51130.