fixes newline bug

Author: pocopepe

src/sed/processor.rs

@@ -567,6 +567,10 @@ fn process_file(
                 'p' => {
                     // Write the pattern space to standard output.
                     write_chunk(output, context, &pattern)?;
+                    if !pattern.is_newline_terminated() {
+                        // !chomped equivalent
+                        output.write_str("\n")?; // explicit \n
+                    }
                 }
                 'P' => {
                     // Output pattern space, up to the first \n.