undefined reference to `tf::Executor::_tear_down_async(tf::Node*)'

[renzhong zhang]

Describe the bug
I think core/executor.hpp should include core/async.hpp

To Reproduce
Steps to reproduce the behavior:
I do include "taskflow/core/executor.hpp" on my cpp file to use tf::Executor executor; when I compile my project catch compile error "undefined reference to `tf::Executor::_tear_down_async(tf::Node*)'"
when I read taskflow/core/executor.hpp code, I find taskflow/core/executor.hpp didn't include core/async.hpp.
I want to know why .
maybe It's a design code for some reason.
the final way to fix this compile error, I need include "taskflow/taskflow.hpp" in my cpp file, but I don't think is the best way for this.

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Additional context

[Tsung-Wei Huang]

You should just include taskflow/taskflow.hpp in your project which will automatically include all necessary files.