Keep dummies in default features for convenience. (#1212)

crates/nu-test-support/Cargo.toml

@@ -15,3 +15,6 @@ dunce = "1.0.0"
 getset = "0.0.9"
 glob = "0.3.0"
 tempfile = "3.1.0"
+
+[build-dependencies]
+nu-build = { version = "0.8.0", path = "../nu-build" }

crates/nu-test-support/build.rs

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