Fix README.md updating part of update_version.sh

I committed that too soon; it works now.

Author: sybrenstuvel

update_version.sh

@@ -9,7 +9,7 @@ DATE=$(date +'%Y-%m-%d')
 
 sed "s/__date__\s=\s\"[^\"]*\"/__date__ = \"$DATE\"/" -i rsa/__init__.py
 sed "s/__version__\s=\s\"[^\"]*\"/__version__ = \"$1\"/" -i rsa/__init__.py
-sed "s+dist/rsa-[\d.]+.tar.gz+__version__ = \"$1\"/" -i README.md
+sed --posix "s/\(dist\/rsa-\)\([0-9.betalphdv-]*[0-9]\)/\1$1/g" -i README.md
 poetry version "$1"
 
 git diff