Fixed warnings with unnecessary usings and forgotten nulls!

SchengenVisaApi/Domains/ApplicantDomain/Applicant.cs

@@ -12,7 +12,7 @@ namespace Domains.ApplicantDomain
         public Name Name { get; set; } = null!;
 
         /// Passport of <see cref="Applicant"/>
-        public Passport Passport { get; set; }
+        public Passport Passport { get; set; } = null!;
 
         /// Date of birth of the <see cref="Applicant"/>
         public DateOnly BirthDate { get; set; }
@@ -42,7 +42,7 @@ namespace Domains.ApplicantDomain
         public Name MotherName { get; set; } = null!;
 
         /// Position of <see cref="Applicant"/>
-        public string JobTitle { get; set; }
+        public string JobTitle { get; set; } = null!;
 
         /// Place of <see cref="Applicant"/>'s work
         public PlaceOfWork PlaceOfWork { get; set; } = null!;

SchengenVisaApi/Infrastructure/Database/Configuration/VisaApplication/VisaApplicationConfiguration.cs

@@ -1,5 +1,4 @@
-using Domains.VisaApplicationDomain;
-using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Metadata.Builders;
 
 namespace Infrastructure.Database.Configuration.VisaApplication

SchengenVisaApi/Infrastructure/Database/DbContext.cs

@@ -1,5 +1,4 @@
 using System.Reflection;
-using Domains;
 using Microsoft.EntityFrameworkCore;
 
 namespace Infrastructure.Database