fix: use fixed playwright version

[vigneshshanmugam]

• Broken by the PW upgrade - fix: update to the latest playwright #485, we have always used to fix the version of PW and reduce the breakage footprint that comes with new versions which might have new system dependencies.
• Without this zip urls monitors that uses the latest version of the Synthetics package will install PW versions that are the latest version 1.23.0 that also requires other system dependencies and fails to invoke the Synthetics.

Produces validation errors like this.

 Host system is missing dependencies to run browsers

║ Please install them with the following command: ║
║ sudo npx playwright install-deps ║
║ Alternatively, use apt: ║
║ sudo apt-get install libwayland-client0 ║

[apmmachine]

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• Start Time: 2022-06-28T00:54:01.673+0000

• Duration: 14 min 43 sec

Test stats 🧪

Test	Results
Failed	0
Passed	167
Skipped	2
Total	169

🤖 GitHub comments

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[andrewvc]

I'm not sure that goes back far enough. I tested that version of playwright by running the current todos demo with a modified package.json shown below in a heartbeat:7.3.0-SNAPSHOT container

{
  "name": "todos",
  "private": true,
  "description": "This suite tests the examples that ship with the open source Vue.js project.",
  "scripts": {},
  "license": "MIT",
  "dependencies": {
    "@elastic/synthetics": "*",
    "playwright-core": "=1.20.1"
  },
  "devDependencies": {
    "node-static": "^0.7.11"
  }
}

I still got the error:

heartbeat@2bc283fe3c0f:/tmp/synthetics-demo/todos/synthetics-tests$ npx @elastic/synthetics .
browserType.launch:
╔══════════════════════════════════════════════════════╗
║ Host system is missing dependencies to run browsers. ║
║ Please install them with the following command:      ║
║                                                      ║
║     sudo npx playwright install-deps                 ║
║                                                      ║
║ Alternatively, use apt:                              ║
║     sudo apt-get install libwayland-client0          ║
║                                                      ║
║ <3 Playwright Team                                   ║
╚══════════════════════════════════════════════════════╝

[andrewvc]

LGTM, pinning both core and chromium fixed it