printing missing binary in the case something is missing. testing later

src/app/build/asciidoctor.rs

@@ -12,9 +12,11 @@ fn exec_command(command: &mut process::Command) -> Result<(), String> {
         }
     } else {
         println!("{}", result.unwrap_err());
-        return Err(
-            "asciidoctor not installed. For more information run docki health!".to_string(),
-        );
+        let binary_name = command.get_args().next();
+        return Err(format!(
+            "{} not installed. For more information run docki health!",
+            binary_name.unwrap_or("Something is")
+        ));
     }
 }
 
@@ -31,11 +33,11 @@ fn asciidoctor_docs(in_path: &str, out_path: &str) -> process::Command {
 fn asciidoctor_slides(in_path: &str, out_path: &str, offline_reveal: bool) -> process::Command {
     let mut command = process::Command::new(format!("asciidoctor-revealjs"));
     let out_dir = parent_path(out_path);
-	let revealjs_path = if offline_reveal {
-		path_between(out_dir.to_string(), "./dist/slides/revealjs".to_string())
-	} else {
-		"https://cdn.jsdelivr.net/npm/reveal.js@5.2.1".to_string()
-	};
+    let revealjs_path = if offline_reveal {
+        path_between(out_dir.to_string(), "./dist/slides/revealjs".to_string())
+    } else {
+        "https://cdn.jsdelivr.net/npm/reveal.js@5.2.1".to_string()
+    };
 
     command
         .arg(format!("{in_path}"))