Auto merge of #8994 - jonhoo:manifest-in-local-deps-meta, r=ehuss

metadata: Supply local path for path dependencies

This is potentially a simpler way to address #7483 than #8988.

/cc https://github.com/rust-lang/rustfmt/issues/4247

Fixes #7483.

diff --cc src/doc/man/generated_txt/cargo-metadata.txt
Simple merge

diff --cc src/doc/src/commands/cargo-metadata.md
Simple merge

diff --cc src/etc/man/cargo-metadata.1
Simple merge

diff --cc tests/testsuite/metadata.rs
Simple merge