Fix inconsistent tool exec help (#50238)

Author: jjonescz

src/Cli/dotnet/CommonArguments.cs

@@ -14,7 +14,6 @@ internal class CommonArguments
         public static DynamicArgument<PackageIdentityWithRange?> OptionalPackageIdentityArgument() =>
             new("packageId")
             {
-                HelpName = "PACKAGE_ID",
                 Description = CliStrings.PackageIdentityArgumentDescription,
                 CustomParser = (ArgumentResult argumentResult) => ParsePackageIdentityWithVersionSeparator(argumentResult.Tokens[0]?.Value),
                 Arity = ArgumentArity.ZeroOrOne,
@@ -23,7 +22,6 @@ internal class CommonArguments
         public static DynamicArgument<PackageIdentityWithRange> RequiredPackageIdentityArgument() =>
             new("packageId")
             {
-                HelpName = "PACKAGE_ID",
                 Description = CliStrings.PackageIdentityArgumentDescription,
                 CustomParser = (ArgumentResult argumentResult) => ParsePackageIdentityWithVersionSeparator(argumentResult.Tokens[0]?.Value)!.Value,
                 Arity = ArgumentArity.ExactlyOne,