fix: adding trialing slash detection logic back in urlToWSEndpoint

[stkevintan]

This PR simply brings the previous behavior back before: eb5e3b3

This commit will break if the url has custom sections:

For chrome cdp, it is possible to get webSocketDebuggerUrl by some verbose path:

[mxschmitt]

I think it would be great to add a test for that, would it be possible to add one - somewhere around here? https://github.com/microsoft/playwright/blob/main/tests/library/chromium/connect-over-cdp.spec.ts

[github-actions]

Test results for "tests 1"

6 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
⚠️ [playwright-test] › ui-mode-test-watch.spec.ts:145:5 › should watch all @ubuntu-latest-node18-1
⚠️ [webkit-library] › library/browsercontext-viewport-mobile.spec.ts:97:5 › mobile viewport › should fire orientationchange event @webkit-ubuntu-22.04-node18
⚠️ [webkit-library] › library/video.spec.ts:475:5 › screencast › should scale frames down to the requested size @webkit-ubuntu-22.04-node18
⚠️ [webkit-page] › page/page-screenshot.spec.ts:345:5 › page screenshot › should work while navigating @webkit-ubuntu-22.04-node18
⚠️ [playwright-test] › ui-mode-test-watch.spec.ts:145:5 › should watch all @windows-latest-node18-1

39442 passed, 823 skipped
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Merge workflow run.