docs(playwright): warn against playwright install-deps without root

[DaveHanns]

Summary

Add a note in the Dockerfile reference explaining that users developing a Playwright Actor locally should not run npx playwright install-deps. That command requires sudo, and in unprivileged environments (agent sandboxes, restricted shells, some CI runners) it fails with a cryptic error and blocks the user from making progress.

The apify/actor-node-playwright-* base images already include every system library Playwright needs, so the workaround is just: rely on the base image via apify run, or push to Apify and run remotely.

Rationale

When a user new to Playwright follows the Playwright docs verbatim and runs the recommended local setup command:

$ npx playwright install-deps
BEWARE: your OS is not officially supported by Playwright; installing dependencies for Ubuntu Jammy (22.04) LTS as a fallback.
Switching to root user to install dependencies...
su: must be suid to work properly
Failed to install browser dependencies

...they hit a dead end. Nothing in the current Dockerfile docs tells them that this step is redundant when using an Apify base image. Adding one small note under the "Node.js base images" section prevents the whole class of "Playwright won't install locally" support questions.

Change

sources/platform/actors/development/actor_definition/docker.md — add a :::note admonition immediately below the Node.js base images table, covering:

• Base images already ship libnss3, libatk1.0-0, etc.
• playwright install-deps requires root and will fail as shown above in unprivileged environments.
• Preferred paths: apify run (uses the base image) or apify push + run remotely.
• npx playwright install (browser binaries only, user-owned dir) is still fine.

Test plan

• Docs page renders the new admonition below the Node.js base images table.
• Links (apify run, apify push) resolve to the CLI reference.
• No typos flagged by typos.toml.

Surfaced during an evaluation of Apify surfaces for agent-driven Actor development.