Generate `has_arabic_joining`

src/Makefile.am

diff --git a/src/Makefile.am b/src/Makefile.am
index c18adac..c341d40 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -248,6 +248,7 @@
 
 
 GENERATORS = \
+	gen-arabic-joining-list.py \
 	gen-arabic-table.py \
 	gen-def.py \
 	gen-emoji-table.py \