(#2220) Add convert command to allowed list

In a future version of Chocolatey Licensed, a new convert command is
going to be introduced, which will work with nupkg files. We are
preemptively adding the convert command in the next release of
Chocolatey, so that we don't have to release another version nearer the
time we ship the convert command.

src/chocolatey.console/Program.cs

@@ -176,7 +176,7 @@ private static void Main(string[] args)
         private static void warn_on_nuspec_or_nupkg_usage(string[] args, ChocolateyConfiguration config)
         {
             var commandLine = Environment.CommandLine;
-            if (!(commandLine.contains(" pack ") || commandLine.contains(" push ")) && (commandLine.contains(".nupkg") || commandLine.contains(".nuspec")))
+            if (!(commandLine.contains(" pack ") || commandLine.contains(" push ") || commandLine.contains("convert")) && (commandLine.contains(".nupkg") || commandLine.contains(".nuspec")))
             {
                 if (config.RegularOutput) "chocolatey".Log().Warn("The use of .nupkg or .nuspec in for package name or source is known to cause issues. Please use the package id from the nuspec `<id />` with `-s .` (for local folder where nupkg is found).");
             }