Apply suggestions from code review

Co-authored-by: Ed Page <eopage@gmail.com>

Author: kornelski

src/cargo/util/toml/mod.rs

@@ -588,18 +588,18 @@ fn normalize_toml(
 }
 
 fn field_requires_package_error(field: &str, has_workspace: bool) -> anyhow::Error {
-    let toml_brackets = if matches!(field, "bin" | "example" | "test" | "bench") {
+    let (table_open, table_close) = if matches!(field, "bin" | "example" | "test" | "bench") {
         ("[[", "]]")
     } else {
         ("[", "]")
     };
-    let toml_table = format_args!("{}{field}{}", toml_brackets.0, toml_brackets.1);
-    let suggest_workspace = has_workspace
-        && matches!(
+    let toml_table = format_args!("{table_open}{field}{table_close}");
+    let inheritable = matches!(
             field,
             "dependencies" | "dev-dependencies" | "build-dependencies" | "lints"
         );
-    let help = if suggest_workspace {
+    let suggest_template = has_workspace && inheritable;
+    let help = if suggest_template {
         format_args!(
             "\nhelp: you can use `[workspace.{field}]` to define a template for workspace members to inherit from"
         )