try to fix template resolvers, step 3

src/main/java/ru/ulstu/configuration/MailTemplateConfiguration.java

@@ -17,6 +17,7 @@ public class MailTemplateConfiguration {
         final SpringTemplateEngine templateEngine = new SpringTemplateEngine();
         templateEngine.addTemplateResolver(templateResolver);
         templateEngine.addTemplateResolver(emailTemplateResolver());
+        templateEngine.addTemplateResolver(mvcTemplateResolver());
         templateEngine.addDialect(new LayoutDialect());
         templateEngine.addDialect(sec);
         return templateEngine;
@@ -32,4 +33,14 @@ public class MailTemplateConfiguration {
         return emailTemplateResolver;
     }
 
+    public ClassLoaderTemplateResolver mvcTemplateResolver() {
+        ClassLoaderTemplateResolver emailTemplateResolver = new ClassLoaderTemplateResolver();
+        emailTemplateResolver.setPrefix("templates/");
+        emailTemplateResolver.setTemplateMode("HTML5");
+        emailTemplateResolver.setSuffix(".html");
+        emailTemplateResolver.setOrder(2);
+        emailTemplateResolver.setCharacterEncoding(StandardCharsets.UTF_8.name());
+        return emailTemplateResolver;
+    }
+
 }