Fix python deprecation warning. (#1018)

It's related to specifying the glob patterns for the file with the
license text.

Author: MarkCallow

interface/python_binding/setup.py

@@ -22,7 +22,7 @@
     include_package_data=True,
     install_requires=["cffi>=1.15.1"],
     license="Apache 2.0",
-    license_files=('LICENSE'),
+    license_files=['LICENSE'],
     long_description_content_type="text/markdown",
     long_description="This Python package provides a Pythonic interface to libktx. It uses CFFI to generate the C bindings.",
     packages=['pyktx'],