public void setSectionProperty(String sectionName, String propertyName, String propertyValue) {
        String name = cleanName(sectionName);
        Section section = getSection(name);
        if (section == null) {
            section = addSection(name);
        }
        section.put(propertyName, propertyValue);
    }
Sets a name/value pair for the section with the given {@code sectionName}.  If the section does not yet exist,
it will be created.  If the {@code sectionName} is null or empty, the name/value pair will be placed in the
default (unnamed, empty string) section.

@param sectionName   the name of the section to add the name/value pair
@param propertyName  the name of the property to add
@param propertyValue the property value
config/core/src/main/java/org/apache/shiro/config/Ini.java