test: move browser._launchServer in child process

[Skn0tt]

The connect call in this test was causing all other browsers in the worker to be closed:

playwright/packages/playwright-core/src/remote/playwrightServer.ts

Lines 257 to 261 in a5daba9

	// In pre-launched mode, keep only the pre-launched browser.
	for (const b of this._playwright.allBrowsers()) {
	if (b !== browser)
	await b.close({ reason: 'Connection terminated' });
	}

To prevent this contamination, i'm moving this test into subprocess, just like all the other tests in the file.

[github-actions]

Test results for "tests 1"

4 flaky

⚠️ [firefox-library] › library/inspector/cli-codegen-1.spec.ts:1079 › cli codegen › should not throw csp directive violation errors `@firefox-ubuntu-22.04-node18`
⚠️ [firefox-page] › page/page-event-request.spec.ts:182 › should return response body when Cross-Origin-Opener-Policy is set `@firefox-ubuntu-22.04-node18`
⚠️ [firefox-page] › page/page-wait-for-function.spec.ts:104 › should work with strict CSP policy `@firefox-ubuntu-22.04-node18`
⚠️ [playwright-test] › ui-mode-test-output.spec.ts:80 › should show console messages for test `@ubuntu-latest-node22-1`

46618 passed, 805 skipped

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Merge workflow run.