prom-client event loop lag

[twoeths]

Describe the bug

Since v1.10.0, prom-client event loop lag increased

this does not link to any performance issue, while the NodeJS event loop lag is consistently great

For the context of these metrics, see #5842

Expected behavior

Investigate how important is this issue, how can we improve it or give a good explanation of it

Steps to reproduce

No response

Additional context

No response

Operating system

Linux

Lodestar version or commit hash

v1.10.0

[twoeths]

dashboard changed, need to reopen if needed