message: Improve precision of host build.rustflags tests
diff: @@ -731,26 +731,6 @@ fn build_rustflags_normal_source_with_target() {
  .with_status(101)
  .with_stderr_contains("[..]bogus[..]")
  .run();
  -
  - // With -Ztarget-applies-to-host build.rustflags should still not apply to build.rs, even when
  - // target == host, to match legacy Cargo behavior.
  - p.change_file("build.rs", "fn main() {}");
  - p.change_file(
  - ".cargo/config",
  - r#"
  - target-applies-to-host = true
  -
  - [build]
  - rustflags = ["-Z", "bogus"]
  - "#,
  - );
  - p.cargo("build --lib --target")
  - .arg(host)
  - .masquerade_as_nightly_cargo()
  - .arg("-Ztarget-applies-to-host")
  - .with_status(101)
  - .with_stderr_does_not_contain("[..]build_script_build[..]")
  - .run();
  }
  #[cargo_test]
  @@ -1161,7 +1141,7 @@ fn build_rustflags_for_build_scripts() {
  // With "legacy" behavior, build.rustflags should apply to build scripts without --target
  p.cargo("build")
  .with_status(101)
  - .with_stderr_does_not_contain("[..]build_script_build[..]")
  + .with_stderr_contains("[..]previous definition of the value `main` here[..]")
  .run();
  // But should _not_ apply _with_ --target
  @@ -1172,7 +1152,7 @@ fn build_rustflags_for_build_scripts() {
  .masquerade_as_nightly_cargo()
  .arg("-Ztarget-applies-to-host")
  .with_status(101)
  - .with_stderr_does_not_contain("[..]build_script_build[..]")
  + .with_stderr_contains("[..]previous definition of the value `main` here[..]")
  .run();
  p.cargo("build --target")
  .arg(host)
  