enable py-siibra tests

packages/py-siibra/package.py

@@ -32,11 +32,12 @@ class PySiibra(PythonPackage):
     depends_on('py-typing-extensions',    type=('build', 'run'), when='^python@:3.7')
     depends_on('py-filelock',             type=('build', 'run'))
 
-    depends_on('py-pytest', type='test')
-
-    # @run_after('install')
-    # @on_package_attributes(run_tests=True)
-    # def install_test(self): 
-    #     with working_dir('spack-test', create=True):
-    #         pytest("-rx")
+    depends_on('py-pytest',               type=('test'))
+
+    @run_after('install')
+    @on_package_attributes(run_tests=True)
+    def install_test(self): 
+        with working_dir('spack-test', create=True):
+            pytest = which("pytest")
+            pytest("-rx")