Remove pregenerated Cython C sources

(cherry picked from commit 886aca2168ecd118e76518792d1dd6e10ff52d6b)

python-lxml.spec

@@ -7,7 +7,7 @@ The latest release works with all CPython versions from 2.7 to 3.7.
 
 Name:           python-%{modname}
 Version:        4.7.1
-Release:        3
+Release:        4
 Summary:        XML processing library combining libxml2/libxslt with the ElementTree API
 License:        BSD
 URL:            https://files.pythonhosted.org
@@ -32,6 +32,8 @@ BuildRequires:  python3-devel python3-setuptools python3-Cython
 
 %prep
 %autosetup -n %{modname}-%{version} -p1
+# Remove pregenerated Cython C sources
+find -type f -name '*.c' -print -delete
 
 %build
 export WITH_CYTHON=true
@@ -53,6 +55,9 @@ make test3
 %doc README.rst src/lxml/isoschematron/resources/xsl/iso-schematron-xslt1/readme.txt
 
 %changelog
+* Mon Jul 25 2022 shixuantong <shixuantong@h-partners.com> - 4.7.1-4
+- Remove pregenerated Cython C sources
+
 * Thu Jul 21 2022 renhongxun <renhongxun@h-partners.com> - 4.7.1-3
 - fix CVE-2022-2309