Missing documentation for the --ignore-workspace option

[laesse]

I did not find a reference to the --ignore-worksapce option on the docs page.
This option skips the check for a pnpm-workspace.yaml in a parent directory, this is very useful if you're migrating an existing monorepo, incrementally into a pnpm workspace.
The only place outside the code where I found a reference was this GitHub discussion thread and the changelog entry for version 6.25.0

[MoazAlkharfan]

Hello!
Every line missing from the documentation accumulates wasted time for multiple people using pnpm
Please keep the documentation updated <3