Missing ApiCompat changes

src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt

@@ -45,7 +45,7 @@ System.CommandLine
     public static Argument<System.IO.DirectoryInfo> AcceptExistingOnly(this Argument<System.IO.DirectoryInfo> argument)
     public static Argument<System.IO.FileSystemInfo> AcceptExistingOnly(this Argument<System.IO.FileSystemInfo> argument)
     public static Argument<T> AcceptExistingOnly<T>(this Argument<T> argument)
-  public class Command : IdentifierSymbol, System.Collections.Generic.IEnumerable<Symbol>, System.Collections.IEnumerable, System.CommandLine.Completions.ICompletionSource
+  public class Command : IdentifierSymbol, System.Collections.Generic.IEnumerable<Symbol>, System.Collections.IEnumerable
     .ctor(System.String name, System.String description = null)
     public System.Collections.Generic.IReadOnlyList<Argument> Arguments { get; }
     public System.Collections.Generic.IEnumerable<Symbol> Children { get; }
@@ -109,7 +109,7 @@ System.CommandLine
     .ctor()
     .ctor(System.String message, System.Exception innerException)
   public static class CompletionSourceExtensions
-    public static System.Void Add(this System.Collections.Generic.ICollection<System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem>>> completionSources, System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.String>> complete)
+    public static System.Void Add(this System.Collections.Generic.ICollection<System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem>>> completionSources, System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.String>> completionsDelegate)
     public static System.Void Add(this System.Collections.Generic.ICollection<System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem>>> completionSources, System.String[] completions)
   public static class ConsoleExtensions
     public static System.Void Write(this IConsole console, System.String value)

src/System.CommandLine/OptionValidation.cs

@@ -2,8 +2,6 @@
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
 using System.Collections.Generic;
-using System.CommandLine.Parsing;
-using System.CommandLine.Completions;
 using System.IO;
 
 namespace System.CommandLine