doc: promote `0x` to tier 4
Hey
Context
The diagnostic working group currently works on an initiative to re-evaluate the diagnostic tooling list and its maturity.
Note: it's normally the last batch of updates before closing the issue.
Updated
In the previous instance, we examined the case of the 0x
module: issue link.
The tool is widely used in the field and the latest Node.js version is supported. We’ve decided to move it to Tier 4
But in case you have a different opinion, please share your thoughts in this PR
With love
cc @nodejs/diagnostics