add spack post-installation testing

This Merge Request:

• adds or fixes tests for most EBRAINS (top-level) Spack packages
• adapts gitlab CI and installation script to run tests at installation time

packages/py-bct/package.py

+# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+from spack import *
+
+
+class PyBct(PythonPackage):
+    """
+    Requirement necessary for py-tvb-framework package.
+    """
+
+    homepage = "https://pypi.org/project/bctpy/"
+    pypi = 'bctpy/bctpy-0.6.0.tar.gz '
+
+    maintainers = ['paulapopa', 'ldomide']
+
+    version('0.6.0', '36392049ec5a2ccae75a0cf89b21838fda41a351c31fe6c6622cfcff1c997933')
+
+    # python_requires
+    depends_on('python@3.8:', type=('build', 'run'))
+
+    # setup_requires
+    depends_on('py-pip', type=('build'))
+    depends_on('py-setuptools', type='build')
+    depends_on('py-numpy', type=('build', 'run'))
+    depends_on('py-scipy', type=('build', 'run'))
+    depends_on('py-tox', type=('build', 'run'))
+    depends_on('py-duecredit', type=('build', 'run'))
+
+    depends_on('py-pytest', type='test')
+