guix: Package codesigning tools

contrib/guix/patches/oscrypto-hard-code-openssl.patch

@@ -0,0 +1,13 @@
+diff --git a/oscrypto/__init__.py b/oscrypto/__init__.py
+index eb27313..371ab24 100644
+--- a/oscrypto/__init__.py
++++ b/oscrypto/__init__.py
+@@ -302,3 +302,8 @@ def load_order():
+         'oscrypto._win.tls',
+         'oscrypto.tls',
+     ]
++
++
++paths = '@GUIX_OSCRYPTO_USE_OPENSSL@'.split(',')
++assert len(paths) == 2, 'Value for OSCRYPTO_USE_OPENSSL env var must be two paths separated by a comma'
++use_openssl(*paths)