BLD Add DISTDIR variable. ### Description

Adds `DISTDIR` env variable that points to the directory where libraries should be copied to when building shared libraries with recipe.

### Checklists

- [x] Add new / update outdated documentation

package:
  name: tomli
  version: 2.0.1
  top-level:
    - tomli
source:
  url: https://files.pythonhosted.org/packages/97/75/10a9ebee3fd790d20926a90a2547f0bf78f371b2f13aa822c759680ca7b9/tomli-2.0.1-py3-none-any.whl
  sha256: 939de3e7a6161af0c887ef91b7d41a53e7c5a1ca976325f429cb46ea9bc30ecc
about:
  PyPI: https://pypi.org/project/tomli
  summary: A lil' TOML parser

package:
  name: tomli
  version: 2.0.1
  top-level:
    - tomli
source:
  url: https://files.pythonhosted.org/packages/97/75/10a9ebee3fd790d20926a90a2547f0bf78f371b2f13aa822c759680ca7b9/tomli-2.0.1-py3-none-any.whl
  sha256: 939de3e7a6161af0c887ef91b7d41a53e7c5a1ca976325f429cb46ea9bc30ecc
about:
  PyPI: https://pypi.org/project/tomli
  summary: A lil' TOML parser
