Change tag value because having space in it is not compliant. Update …

…code examples to better match rule implementation

rules/S6863/java/metadata.json

@@ -8,7 +8,7 @@
   },
   "tags": [
     "spring",
-    "best practice"
+    "best-practice"
   ],
   "defaultSeverity": "Major",
   "ruleSpecification": "RSPEC-6863",

rules/S6863/java/rule.adoc

@@ -4,7 +4,7 @@ The request handler function in a `Controller` should set the appropriate HTTP s
 This is done by returning a `Response` object with the appropriate status code.
 
 If an exception is thrown during the execution of the handler, the status code should be in the range of 4xx or 5xx.
-If no exception is thrown, the status code should be in the range of 2xx or 4xx.
+If no exception is thrown, the status code should be in the range of 2xx.
 
 == How to fix it
 
@@ -20,10 +20,8 @@ public class UserController {
         try {
             User user = userService.getUserById(userId);
             return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(user); // Noncompliant: Setting 500 for a successful operation
-        } catch (NotFoundException e) {
-            return ResponseEntity.status(HttpStatus.OK).build(); // Noncompliant: Set 200 for resource not found
         } catch (Exception e) {
-            return ResponseEntity.status(HttpStatus.NOT_FOUND).build(); // Noncompliant: Set 404 for other exceptions
+            return ResponseEntity.status(HttpStatus.OK).build(); // Noncompliant: Set 200 for exception
         }
     }
 }
@@ -35,15 +33,12 @@ public class UserController {
 ----
 @Controller
 public class UserController {
-
     public ResponseEntity<User> getUserById(Long userId) {
         try {
             User user = userService.getUserById(userId);
             return ResponseEntity.ok(user); // Compliant: Set 200 for success
-        } catch (NotFoundException e) {
-            return ResponseEntity.status(HttpStatus.NOT_FOUND).build(); // Compliant: Set 404 for resource not found
         } catch (Exception e) {
-            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build(); // Compliant: Set 500 for other exceptions
+            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build(); // Compliant: Set 400 or 500 for exceptions
         }
     }
 }