Update JDBC file naming in MySQL steup instruction

Author: vladfau

src/main/resources/db/mysql/petclinic_db_setup_mysql.txt

@@ -19,6 +19,6 @@
 3) Create the PetClinic database and user by executing the "db/mysql/createDB.txt"
    script.
 
-4) Open "src/main/resources/spring/jdbc.properties"; comment out all properties in the
+4) Open "src/main/resources/spring/data-access.properties"; comment out all properties in the
    "HSQL Settings" section; uncomment all properties in the "MySQL Settings"
-   section.
+   section.