sci-mathematics/alectryon: fix setup.cfg; add DISTUTILS_USE_PEP517

Bug: https://github.com/cpitclaudel/alectryon/pull/80
Closes: https://bugs.gentoo.org/836748
Signed-off-by: Maciej Barć <xgqt@gentoo.org>

sci-mathematics/alectryon/alectryon-1.4.0-r1.ebuild

@@ -3,6 +3,7 @@
 
 EAPI=8
 
+DISTUTILS_USE_PEP517=setuptools
 PYTHON_COMPAT=( python3_{8..10} )
 
 inherit elisp-common distutils-r1
@@ -42,6 +43,7 @@ BDEPEND="
 "
 
 DOCS=( CHANGES.rst CITATION.bib README.rst )
+PATCHES=( "${FILESDIR}"/${P}-setup.cfg-version.patch )
 SITEFILE="50${PN}-gentoo.el"
 
 src_compile() {

sci-mathematics/alectryon/files/alectryon-1.4.0-setup.cfg-version.patch

@@ -0,0 +1,11 @@
+index 1a25a92..066089b 100644
+--- a/setup.cfg
++++ b/setup.cfg
+@@ -1,6 +1,6 @@
+ [metadata]
+ name = alectryon
+-version = attr: alectryon.__version__
++version = attr: alectryon.__init__.__version__
+ description = A library to process Coq snippets embedded in documents, showing goals and messages for each Coq sentence.
+ long_description = file: README.rst
+ url = https://github.com/cpitclaudel/alectryon