refactor: streamline address validation in EuiccConfiguredAddresses by consolidating checks into a single function

libs/lpac-jni/src/main/java/net/typeblog/lpac_jni/EuiccConfiguredAddresses.kt

@@ -15,7 +15,7 @@ data class EuiccConfiguredAddresses(
 
 private fun isValid(address: String): Boolean {
     if (address.isBlank()) return false
-    if (address.endsWith("gsma.com")) return false
-    if (address.endsWith("example.com")) return false
+    if (address.endsWith(".gsma.com")) return address == "lpa.ds.gsma.com"
+    if (address.endsWith(".example.com")) return false
     return Patterns.DOMAIN_NAME.matcher(address).matches()
 }