remove requirements file

Author: gijzelaerr

cwl_utils/requirements.txt

@@ -1,11 +1,20 @@
 from setuptools import setup, find_packages
 
+
+setup_requires = [
+    'ruamel.yaml',
+    'six',
+    'requests',
+    'cachecontrol',
+    'schema_salad',
+]
+
 setup(
     name='cwl-utils',
     version='0.1',
     author='Common workflow language working group',
     author_email='[email protected]',
     packages=find_packages(),
     python_requires='>=3.6',
-    setup_requires=['ruamel.yaml', 'six'],
+    setup_requires=setup_requires,
 )