patch 9.0.1448: diff test fails on MacOS 13

Problem:    Diff test fails on MacOS 13.
Solution:   Install GNU diffutils. (Ozaki Kiichi, closes vim#12258)

Author: ichizok

.cirrus.yml

@@ -36,7 +36,7 @@ macos_task:
   timeout_in: 20m
   install_script:
     - brew update
-    - brew install gettext libtool
+    - brew install gettext libtool diffutils
   build_script:
     - NPROC=$(getconf _NPROCESSORS_ONLN)
     - ./configure --with-features=${FEATURES}

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1448,
 /**/
     1447,
 /**/