patch 9.1.1506: tests: missing cleanup in Test_search_cmdline_incsearch_highlight()

Problem:  tests: missing cleanup test_override('char_avail', 0) in
          Test_search_cmdline_incsearch_highlight().
Solution: Add the missing cleanup (zeertzjq).

closes: #17655

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/testdir/test_search.vim

@@ -843,6 +843,7 @@ func Test_search_cmdline_incsearch_highlight()
 
   " clean up
   set noincsearch nohlsearch
+  call test_override("char_avail", 0)
   bw!
 endfunc
 

src/version.c

@@ -719,6 +719,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1506,
 /**/
     1505,
 /**/