[shelly] Fix suggestion finder

[jlaur]

My PM Mini is discovered as name starting with "shelly" (lowercase):

Making the matching case-insensitive is consistent with the logic in code:

openhab-addons/bundles/org.openhab.binding.shelly/src/main/java/org/openhab/binding/shelly/internal/discovery/ShellyDiscoveryParticipant.java

Lines 95 to 99 in 18862d3

	public DiscoveryResult createResult(final ServiceInfo service) {
	String name = service.getName().toLowerCase(); // Shelly Duo: Name starts with" Shelly" rather than "shelly"
	if (!name.startsWith("shelly")) {
	return null;
	}

Regression of #15817

[holgerfriedrich]

LGTM