Fix ConfigurationPropertyName.equals

Fix a regression in `ConfigurationPropertyName.equals` that was causing
incorrect results.

Closes gh-14665

Author: philwebb

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/properties/source/ConfigurationPropertyName.java

@@ -348,7 +348,7 @@ else if (ch1 != ch2) {
 		}
 		while (i2 < l2) {
 			char ch2 = e2.charAt(i, i2++);
-			if (indexed2 || !ElementsParser.isAlphaNumeric(ch2)) {
+			if (indexed2 || ElementsParser.isAlphaNumeric(ch2)) {
 				return false;
 			}
 		}