Update setup.cfg

    * Install the toml extra_requires for setuptools_scm in setup_requires

Signed-off-by: Jono Yang <jyang@nexb.com>

Author: JonoYang

setup.cfg

@@ -34,7 +34,7 @@ install_requires =
     intbitset >= 2.3.0, < 3.0
     saneyaml
     typing >=3.6, < 3.7
-setup_requires = setuptools_scm >= 4
+setup_requires = setuptools_scm[toml] >= 4
 
 [options.packages.find]
 where=src