add small fixes

src/Nager.PublicSuffix.WebApi/Models/Author.cs

@@ -4,6 +4,6 @@ public class Author
     {
         public string? Name { get; set; }
         public string? Email { get; set; }
-        public DateTime Date { get; set; }
+        public DateTime? Date { get; set; }
     }
 }

src/Nager.PublicSuffix.WebApi/Models/CommitInfo.cs

@@ -2,11 +2,11 @@
 {
     public class CommitInfo
     {
-        public Author Author { get; set; }
-        public Committer Committer { get; set; }
+        public Author? Author { get; set; }
+        public Committer? Committer { get; set; }
         public string? Message { get; set; }
-        public Tree Tree { get; set; }
+        public Tree? Tree { get; set; }
         public string? Url { get; set; }
-        public Verification Verification { get; set; }
+        public Verification? Verification { get; set; }
     }
 }

src/Nager.PublicSuffix.WebApi/Models/Committer.cs

@@ -4,6 +4,6 @@ public class Committer
     {
         public string? Name { get; set; }
         public string? Email { get; set; }
-        public DateTime Date { get; set; }
+        public DateTime? Date { get; set; }
     }
 }

src/Nager.PublicSuffix.WebApi/Models/GitHubCommit.cs

@@ -4,7 +4,7 @@
     public class GitHubCommit
     {
         public string? Sha { get; set; }
-        public CommitInfo Commit { get; set; }
-        public File[] Files { get; set; }
+        public CommitInfo? Commit { get; set; }
+        public File[]? Files { get; set; }
     }
 }

src/Nager.PublicSuffix.WebApi/Models/Verification.cs

@@ -2,7 +2,7 @@
 {
     public class Verification
     {
-        public bool Verified { get; set; }
+        public bool Verified { get; set; } = false;
         public string? Reason { get; set; }
         public string? Signature { get; set; }
         public string? Payload { get; set; }

src/Nager.PublicSuffix.WebApi/Program.cs

@@ -54,7 +54,7 @@
     httpClient.DefaultRequestHeaders.Add("User-Agent", "Nager.PublicSuffix");
     var lastGitHubCommit = await httpClient.GetFromJsonAsync<GitHubCommit>("https://api.github.com/repos/publicsuffix/list/commits/master");
 
-    return lastGitHubCommit.Commit.Committer.Date;
+    return lastGitHubCommit?.Commit?.Committer?.Date;
 })
 .WithName("CheckLastCommit")
 .WithOpenApi();