fix #2393 update eol date

src/main/java/org/codelibs/fess/helper/SystemHelper.java

@@ -117,7 +117,7 @@ public class SystemHelper {
             logger.debug("Initialize {}", this.getClass().getSimpleName());
         }
         final Calendar cal = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
-        cal.set(2021, 6 - 1, 2); // EOL Date
+        cal.set(2021, 8 - 1, 11); // EOL Date
         eolTime = cal.getTimeInMillis();
         if (isEoled()) {
             logger.error("Your system is out of support. See https://fess.codelibs.org/eol.html");