Revert "[conda] Try to get rid of project_dir conda template variable"

This reverts commit 6eeb9aa5.

conda/meta.yaml

 {% set name = 'bob.devtools' %}
+{% set project_dir = environ.get('RECIPE_DIR') + '/..' %}
 
 package:
   name: {{ name }}
@@ -11,7 +12,7 @@ build:
   run_exports:
     - {{ pin_subpackage(name) }}
   script:
-    - cd {{ environ.get('RECIPE_DIR') + '/..' }}
+    - cd {{ project_dir }}
     {% if environ.get('BUILD_EGG') %}
     - python setup.py sdist --formats=zip
     {% endif %}
@@ -67,7 +68,7 @@ test:
     - bdt ci build --help
     - bdt ci deploy --help
     - bdt ci pypi --help
-    - sphinx-build -aEW ${PREFIX}/share/doc/{{ name }}/doc sphinx
+    - sphinx-build -aEW ${PREFIX}/share/doc/{{ name }}/doc {{ project_dir }}/sphinx
 
 about:
   home: https://www.idiap.ch/software/bob/