Describe the bug

It was pointed out in #11726 that the Meson build of Nix depends on Nix:

This is fine when the manual is built in its own derivation, but not when it's built in a dev shell or a single derivation. In the old build system, the manual has a make rule that causes it to depend on the nix binary from the same build process.

Steps To Reproduce

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4. See error

Expected behavior

A clear and concise description of what you expected to happen.

nix-env --version output

Additional context

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