Make Airport - City relationship bidirectional

core/src/main/java/cz/muni/fi/pa165/core/data/domain/City.java

@@ -6,11 +6,13 @@ import jakarta.persistence.Entity;
 import jakarta.persistence.FetchType;
 import jakarta.persistence.JoinColumn;
 import jakarta.persistence.ManyToOne;
+import jakarta.persistence.OneToMany;
 import jakarta.persistence.Table;
 import lombok.Data;
 import lombok.NoArgsConstructor;
 import lombok.NonNull;
 
+import java.util.Collection;
 import java.util.Objects;
 
 @Entity
@@ -26,7 +28,8 @@ public class City extends DomainEntity {
     @JoinColumn(name = "country_id")
     private Country country;
 
-    // TODO: Add relationship City - Airport
+    @OneToMany(fetch = FetchType.LAZY, mappedBy = "city")
+    private Collection<Airport> airports;
 
     @Override
     public boolean equals(Object o) {