Fix license configuration in pyproject.toml to resolve CI twine check error

Co-authored-by: mrecachinas <924243+mrecachinas@users.noreply.github.com>

Author: Copilot

pyproject.toml

@@ -7,7 +7,6 @@ name = "hexhamming"
 dynamic = ["version"]
 description = "Fast Hamming distance calculation for hexadecimal strings"
 readme = "README.rst"
-license = {file = "LICENSE"}
 authors = [
     {name = "Michael Recachinas", email = "m.recachinas@gmail.com"}
 ]
@@ -32,6 +31,7 @@ dev = [
 
 [tool.setuptools]
 zip-safe = false
+license-files = ["LICENSE"]
 
 [tool.setuptools.packages.find]
 include = ["hexhamming*"]