patch 8.2.4548: script-local function is deleted when used in a funcref

Problem:    Script-local function is deleted when used in a funcref.
Solution:   Do not consider a function starting with "<SNR>" reference
            counted. (closes #9916, closes #9820)
diff --git a/src/version.c b/src/version.c
index eec3622..2efc6bf 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4548,
+/**/
     4547,
 /**/
     4546,