Set relative path to artifacts and cache

This MR solves an issue relative to CI paths for artifacts and caches that must be relative (and are enforced on Linux shell runners). This is not required by this package, but better to be preventive.

.gitlab-ci.yml

@@ -3,7 +3,8 @@
 
 # Definition of global variables (all stages)
 variables:
-  CONDA_ROOT: "${CI_PROJECT_DIR}/miniconda"
+  MINICONDA_DIR: "miniconda"
+  CONDA_ROOT: "${CI_PROJECT_DIR}/${MINICONDA_DIR}"
 
 
 # Definition of our build pipeline order
@@ -29,8 +30,8 @@ stages:
   cache: &build_caches
     paths:
       - miniconda.sh
-      - ${CONDA_ROOT}/pkgs/*.tar.bz2
-      - ${CONDA_ROOT}/pkgs/urls.txt
+      - ${MINICONDA_DIR}/pkgs/*.tar.bz2
+      - ${MINICONDA_DIR}/pkgs/urls.txt
 
 
 .build_linux_template: &linux_build_job
@@ -42,7 +43,7 @@ stages:
     expire_in: 1 week
     paths:
       - _ci/
-      - ${CONDA_ROOT}/conda-bld/linux-64/*.tar.bz2
+      - ${MINICONDA_DIR}/conda-bld/linux-64/*.tar.bz2
   cache:
     <<: *build_caches
     key: "linux-cache"
@@ -56,7 +57,7 @@ stages:
     expire_in: 1 week
     paths:
       - _ci/
-      - ${CONDA_ROOT}/conda-bld/osx-64/*.tar.bz2
+      - ${MINICONDA_DIR}/conda-bld/osx-64/*.tar.bz2
   cache:
     <<: *build_caches
     key: "macosx-cache"
@@ -73,7 +74,7 @@ build_linux_36:
       - _ci/
       - dist/*.zip
       - sphinx
-      - ${CONDA_ROOT}/conda-bld/linux-64/*.tar.bz2
+      - ${MINICONDA_DIR}/conda-bld/linux-64/*.tar.bz2
 
 
 build_macosx_36: