title: When do you need curly braces for variable substitution in Gradle?
body: <p>If you have variables defined in your <code>gradle.properties</code> file, when is it necessary to use curly braces for variable substitution (e.g., <code>"some string ${yourVariable}"</code>) and when is it okay to do without (e.g., <code>"some string $yourVariable"</code>). Is it considered best practice to always use curly braces?</p>