Remove build.rs and nu-build (#2282)

crates/nu_plugin_fetch/Cargo.toml

@@ -20,4 +20,3 @@ surf = "1.0.3"
 url = "2.1.1"
 
 [build-dependencies]
-nu-build = {version = "0.17.0", path = "../nu-build"}

crates/nu_plugin_fetch/build.rs

@@ -1,3 +0,0 @@
-fn main() -> Result<(), Box<dyn std::error::Error>> {
-    nu_build::build()
-}