minor refactoring

Spr24/HW/Homework3/README.md

@@ -7,6 +7,8 @@
 Note that question 3 does not have an input/output file. Instead, it has a testing code file that runs some tests.
 You can run the test by running the following command in the terminal:
 
-```smlnj test_parse.sml```
+```
+smlnj test_parse.sml
+```
 
 You may notice that the first line in the test file is `use "hw3_q3.sml"`, which means that your solution file must be accessible in the working directory. If you have your solution in a different directory, you can change the path in the test file.