chore: don't close other browsers in reuse-browsers mode

[Skn0tt]

There's no need to manipulate other browsers on this._playwright upon disconnect. And the !browser.contexts() clause was busted all along - I replaced it with a comment.

[github-actions]

Test results for "tests 1"

1 failed
❌ [webkit-library] › library/browsercontext-viewport-mobile.spec.ts:87:5 › mobile viewport › should support window.orientation emulation @webkit-ubuntu-22.04-node18

4 flaky

⚠️ [firefox-library] › library/inspector/cli-codegen-1.spec.ts:986:7 › cli codegen › should not throw csp directive violation errors @firefox-ubuntu-22.04-node18
⚠️ [firefox-page] › page/page-wait-for-function.spec.ts:104:3 › should work with strict CSP policy @firefox-ubuntu-22.04-node18
⚠️ [playwright-test] › ui-mode-test-watch.spec.ts:145:5 › should watch all @ubuntu-latest-node22-1
⚠️ [webkit-library] › library/browsercontext-viewport-mobile.spec.ts:97:5 › mobile viewport › should fire orientationchange event @webkit-ubuntu-22.04-node18

39449 passed, 823 skipped
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Merge workflow run.