fix nullable de-reference on Created.

Author: BryanAldrich

modules/openapi-generator/src/main/resources/csharp/auth/TokenResponse.mustache

@@ -19,6 +19,6 @@ namespace {{packageName}}.Client.Auth
         [JsonProperty("refresh_token")]
         public string{{nrt?}} RefreshToken { get; set; }
 
-        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created.AddSeconds(ExpiresIn.Value);
+        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created?.AddSeconds(ExpiresIn.Value);
     }
 }

samples/client/petstore/csharp/restsharp/net4.7/MultipleFrameworks/src/Org.OpenAPITools/Client/Auth/TokenResponse.cs

@@ -27,6 +27,6 @@ class TokenResponse
         [JsonProperty("refresh_token")]
         public string RefreshToken { get; set; }
 
-        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created.AddSeconds(ExpiresIn.Value);
+        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created?.AddSeconds(ExpiresIn.Value);
     }
 }

samples/client/petstore/csharp/restsharp/net4.7/Petstore/src/Org.OpenAPITools/Client/Auth/TokenResponse.cs

@@ -27,6 +27,6 @@ class TokenResponse
         [JsonProperty("refresh_token")]
         public string RefreshToken { get; set; }
 
-        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created.AddSeconds(ExpiresIn.Value);
+        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created?.AddSeconds(ExpiresIn.Value);
     }
 }

samples/client/petstore/csharp/restsharp/net4.8/Petstore/src/Org.OpenAPITools/Client/Auth/TokenResponse.cs

@@ -27,6 +27,6 @@ class TokenResponse
         [JsonProperty("refresh_token")]
         public string RefreshToken { get; set; }
 
-        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created.AddSeconds(ExpiresIn.Value);
+        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created?.AddSeconds(ExpiresIn.Value);
     }
 }

samples/client/petstore/csharp/restsharp/net7/EnumMappings/src/Org.OpenAPITools/Client/Auth/TokenResponse.cs

@@ -27,6 +27,6 @@ class TokenResponse
         [JsonProperty("refresh_token")]
         public string? RefreshToken { get; set; }
 
-        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created.AddSeconds(ExpiresIn.Value);
+        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created?.AddSeconds(ExpiresIn.Value);
     }
 }

samples/client/petstore/csharp/restsharp/net7/Petstore/src/Org.OpenAPITools/Client/Auth/TokenResponse.cs

@@ -27,6 +27,6 @@ class TokenResponse
         [JsonProperty("refresh_token")]
         public string? RefreshToken { get; set; }
 
-        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created.AddSeconds(ExpiresIn.Value);
+        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created?.AddSeconds(ExpiresIn.Value);
     }
 }

samples/client/petstore/csharp/restsharp/standard2.0/ConditionalSerialization/src/Org.OpenAPITools/Client/Auth/TokenResponse.cs

@@ -27,6 +27,6 @@ class TokenResponse
         [JsonProperty("refresh_token")]
         public string RefreshToken { get; set; }
 
-        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created.AddSeconds(ExpiresIn.Value);
+        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created?.AddSeconds(ExpiresIn.Value);
     }
 }

samples/client/petstore/csharp/restsharp/standard2.0/Petstore/src/Org.OpenAPITools/Client/Auth/TokenResponse.cs

@@ -27,6 +27,6 @@ class TokenResponse
         [JsonProperty("refresh_token")]
         public string RefreshToken { get; set; }
 
-        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created.AddSeconds(ExpiresIn.Value);
+        public DateTime? ExpiresAt => ExpiresIn == null ? null : Created?.AddSeconds(ExpiresIn.Value);
     }
 }