docs: document file bindings

[barmac]

Proposed Changes

This adds missing links on file type bindings.
To check: Do we still need them on Windows? How does it work on Linux?

Checklist

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• Brief textual description of the changes present
• Visual demo attached
• Steps to try out present, i.e. using the @bpmn-io/sr tool
• Related issue linked via Closes {LINK_TO_ISSUE} or Related to {LINK_TO_ISSUE}