Fix typo (eugenp#4897)

* add new module

* fix typo

Author: lor6

spring-boot/src/main/java/org/baeldung/common/error/MyCustomErrorController.java

@@ -13,7 +13,7 @@ public MyCustomErrorController() {
 
     @GetMapping(value = PATH)
     public String error() {
-        return "Error heaven";
+        return "Error haven";
     }
 
     @Override

spring-boot/src/main/java/org/baeldung/common/error/controller/ErrorController.java

@@ -14,9 +14,9 @@ String error400() {
         return "Error Code: 400 occured.";
     }
 
-    @GetMapping("/errorHeaven")
+    @GetMapping("/errorHaven")
     String errorHeaven() {
-        return "You have reached the heaven of errors!!!";
+        return "You have reached the haven of errors!!!";
     }
 
 }

spring-boot/src/main/java/org/baeldung/common/properties/MyServletContainerCustomizationBean.java

@@ -19,7 +19,7 @@ public void customize(ConfigurableServletWebServerFactory container) {
         container.setContextPath("/springbootapp");
 
         container.addErrorPages(new ErrorPage(HttpStatus.BAD_REQUEST, "/400"));
-        container.addErrorPages(new ErrorPage("/errorHeaven"));
+        container.addErrorPages(new ErrorPage("/errorHaven"));
     }
 
 }