fix tool error message to refer to Werror instead of fatal warning

Author: Oron Port

lib/src/main/scala/dfhdl/tools/toolsCore/Tool.scala

@@ -143,7 +143,7 @@ trait Tool:
     if (errCode != 0 || hasWarnings && summon[ToolOptions].Werror.toBoolean)
       val msg =
         if (errCode != 0) s"${toolName} exited with the error code ${errCode}."
-        else s"${toolName} exited with warnings while `fatal warnings` is turned on."
+        else s"${toolName} exited with warnings while `Werror-tool` is turned on."
       error(
         s"""|$msg
             |Path: ${Paths.get(execPath).toAbsolutePath()}