pySCG: fix pyproject.toml readme path for build

Change readme reference from 'README.md' to 'tests/README.md' to match
actual file location and fix build error in CI.

Signed-off-by: tommcd <[email protected]>

Author: tommcd

docs/Secure-Coding-Guide-for-Python/pyproject.toml

@@ -2,7 +2,7 @@
 name = "secure-coding-guide-python-tests"
 version = "0.1.0"
 description = "Testing framework for Python Secure Coding Guide"
-readme = "README.md"
+readme = "tests/README.md"
 requires-python = ">=3.9"
 
 [build-system]