CLAP-355 Fix: validation 오류 수정

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- #448

Author: joowojr

src/main/java/clap/server/domain/policy/member/ManagerDepartmentPolicy.java

@@ -9,9 +9,10 @@
 @Policy
 public class ManagerDepartmentPolicy {
     public void validateDepartment(final Department department, final MemberRole memberRole) {
-        if (!(department.isManager()
-                && memberRole == MemberRole.ROLE_MANAGER)) {
-            throw new DomainException(MemberErrorCode.MANAGER_PERMISSION_DENIED);
+        if (!department.isManager() ){
+            if(memberRole == MemberRole.ROLE_MANAGER){
+                throw new DomainException(MemberErrorCode.MANAGER_PERMISSION_DENIED);
+            }
         }
     }
 }