fix(mail): lookup UTF-8 support config in static method to pick up ch…

…anged value during tests

Also switch to safer lookup via codepoint comparison to 7bit = chars < 128 in favor over encoder

src/main/java/edu/harvard/iq/dataverse/validation/EMailValidator.java

@@ -6,15 +6,11 @@
 
 import org.apache.commons.validator.routines.EmailValidator;
 
-import java.nio.charset.StandardCharsets;
-
 /**
  *
  * @author skraffmi
  */
 public class EMailValidator implements ConstraintValidator<ValidateEmail, String> {
-
-    private static final boolean MTA_SUPPORTS_UTF8 = JvmSettings.MAIL_MTA_SUPPORT_UTF8.lookup(Boolean.class);
 
     @Override
     public boolean isValid(String value, ConstraintValidatorContext context) {
@@ -28,10 +24,12 @@ public boolean isValid(String value, ConstraintValidatorContext context) {
      * @return true when valid, false when invalid (null = valid!)
      */
     public static boolean isEmailValid(String value) {
+        // Must be looked up here - otherwise changes are not picked up (tests, live config, ...)
+        final boolean mtaSupportsUTF8 = JvmSettings.MAIL_MTA_SUPPORT_UTF8.lookup(Boolean.class);
         return value == null || (EmailValidator.getInstance().isValid(value) &&
             // If the MTA isn't able to handle UTF-8 mail addresses following RFC 6530/6531/6532, we can only declare
             // mail addresses using 7bit ASCII (RFC 821) as valid.
             // Beyond scope for Apache Commons Validator, see also https://issues.apache.org/jira/browse/VALIDATOR-487
-            (StandardCharsets.US_ASCII.newEncoder().canEncode(value) || MTA_SUPPORTS_UTF8) );
+            (value.codePoints().noneMatch(c -> c > 127) || mtaSupportsUTF8) );
     }
 }