twine: use repo name instead of url

scripts/upload-pypi

@@ -8,9 +8,9 @@ if [ "$R" = "" ]; then
 fi
 
 if [ "$2" = "test" ]; then
-    export TWINE_REPOSITORY_URL=https://test.pypi.org/legacy/
+    export TWINE_REPOSITORY=testpypi
 else
-    export TWINE_REPOSITORY_URL=
+    export TWINE_REPOSITORY=pypi
 fi
 
 D=dist/borgbackup-$R.tar.gz