`poller.js` calls `setTimeout` with string argument, which is incompatible with future Content Security Policy restrictions

[daniel-beck]

Jenkins and plugins versions report

n/a

What Operating System are you using (both controller, and any agents involved in the problem)?

n/a

Reproduction steps

1. mvn hpi:run -Djenkins.version=2.537-rc37714.d5718019b_8ff ([JENKINS-76263] Add Content-Security-Policy header jenkins#11269)
2. Create a Dashboard view with Agents stats

Expected Results

JS works, no CSP violations

Actual Results

JS doesn't work, CSP violations

Anything else?

No response

Are you interested in contributing a fix?

Yes