build: fix setup.cfg deprecated values

setup.cfg

@@ -1,21 +1,22 @@
 [metadata]
 name = deepaas
 summary = DEEPaaS is a REST API to expose a machine learning model.
-description-file = README.md
-description-content-type = text/markdown; charset=UTF-8
+description_file = README.md
+description_content_type = text/markdown; charset=UTF-8
 
 author = Alvaro Lopez Garcia
-author-email = aloga@ifca.unican.es
+author_email = aloga@ifca.unican.es
 
-home-page = https://github.com/indigo-dc/deepaas
+home_page = https://github.com/indigo-dc/deepaas
 project_urls =
     Bug Tracker = https://github.com/indigo-dc/deepaas/issues
     Documentation = https://deepaas.readthedocs.io/
 
-python-requires = >=3.6
+python_requires = >=3.6
 
 license = Apache-2
-license_file = LICENSE
+license_files = 
+    LICENSE
 
 classifier =
     Development Status :: 5 - Production/Stable