Don't mention license twice (#30)

The use of license = {file = 'LICENSE'} results in significant ugliness in the sidebar on PyPI. We don't appear to need it, since the license is already specified in the trove classifiers. This PR removes that entry from the pyproject.toml (and also does a drive-by cleanup of the authors field).

(cherry picked from commit df42c43)

pyproject.toml

@@ -7,10 +7,7 @@ name = 'simplefractions'
 description = 'Find the simplest fraction for a given float or interval'
 readme = 'README.md'
 requires-python = '>=3.6'
-license = {file = 'LICENSE'}
-authors = [
-    {name = 'Mark Dickinson', email = '[email protected]'}
-]
+authors = [{name = 'Mark Dickinson', email = '[email protected]'}]
 keywords = ['fractions', 'continued fractions', 'approximation']
 classifiers = [
     'License :: OSI Approved :: Apache Software License',