Incorrect version range specified for docutils dependency

[emil-vdw]

Description

sphinx-mdinclude wrongly states that it is compatible with docutils>=0.16,<1.0 when it depends on the function docutils.io.error_string added in docutils version 0.19.

The dependency range needs to be updated to: docutils>=0.19,<1.0.

Details

To reproduce:

[tool.poetry]
package-mode = false

[tool.poetry.dependencies]
python = "~=3.9"
sphinx-mdinclude = "==0.6.0"
docutils = "==0.16"

poetry run python
>> import sphinx_mdinclude