rust-project: name the binary buck2-rust-project

The name `rust-project` is glamorous but far too generic to be meaningful when
talking about it, and it's not immediately clear what it's even referring to
(imagine searching for it on Google). I think `buck2-rust-project` is *much*
better and also gives a template for follow up tools like e.g. `buck2-cxx-
project`

Signed-off-by: Austin Seipp <aseipp@pobox.com>

integrations/rust-project/Cargo.toml

@@ -7,6 +7,10 @@ readme = "README.md"
 repository = { workspace = true }
 version = "0.0.0"
 
+[[bin]]
+name = "buck2-rust-project"
+path = "src/main.rs"
+
 [dependencies]
 anyhow = { workspace = true }
 clap = { workspace = true }