Build: remove hacky auto-reshim and use official one

[humitos]

(context for this issue #9150 (comment))

The PR that auto-reshims asdf Python when calling pip commands got merged, asdf-community/asdf-python#136. Now, we are able to remove our own code for this and rely on asdf-python plugin to do this in a smarter way than ourselves.

To do this, it's required:

• update the asdf version of our Docker images (https://github.com/rtfd/readthedocs-docker-images/blob/788fd20be1619f25eebce40f7103c02bc016fcd0/Dockerfile#L115)
• remove the hacky code from our builder (

  readthedocs.org/readthedocs/doc_builder/director.py

  Lines 350 to 363 in a5ed8f4

  	# Execute ``asdf reshim python`` if the user is installing a
  	# package since the package may contain an executable
  	# See https://github.com/readthedocs/readthedocs.org/pull/9150#discussion_r882849790
  	for reshim_command in reshim_commands:
  	# Convert tuple/list into set to check reshim command is a
  	# subset of the command itself. This is to find ``pip install``
  	# but also ``pip -v install`` and ``python -m pip install``
  	if reshim_command.issubset(command.split()):
  	environment.run(
  	*["asdf", "reshim", "python"],
  	escape_command=False,
  	cwd=cwd,
  	record=False,
  	)

  )