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- [x] Add new / update outdated documentation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: joblib
  version: 1.2.0
  top-level:
    - joblib

requirements:
  run:
    - distutils

source:
  url: https://files.pythonhosted.org/packages/45/dd/a5435a6902d6315241c48a5343e6e6675b007e05d3738ed97a7a47864e53/joblib-1.2.0.tar.gz
  sha256: e1cee4a79e4af22881164f218d4311f60074197fb707e082e803b61f6d137018
about:
  home: https://joblib.readthedocs.io
  PyPI: https://pypi.org/project/joblib
  summary: Lightweight pipelining with Python functions
  license: BSD

package:
  name: joblib
  version: 1.2.0
  top-level:
    - joblib

requirements:
  run:
    - distutils

source:
  url: https://files.pythonhosted.org/packages/45/dd/a5435a6902d6315241c48a5343e6e6675b007e05d3738ed97a7a47864e53/joblib-1.2.0.tar.gz
  sha256: e1cee4a79e4af22881164f218d4311f60074197fb707e082e803b61f6d137018
about:
  home: https://joblib.readthedocs.io
  PyPI: https://pypi.org/project/joblib
  summary: Lightweight pipelining with Python functions
  license: BSD
