patch 9.0.1263: KDL files are not recognized

Problem:    KDL files are not recognized.
Solution:   Add a pattern for KDL files. (Amaan Qureshi, closes #11898)

runtime/filetype.vim

@@ -1032,6 +1032,9 @@ au BufNewFile,BufRead *.jsonnet,*.libsonnet	setf jsonnet
 " Julia
 au BufNewFile,BufRead *.jl			setf julia
 
+" KDL
+au BufNewFile,BufRead *.kdl			setf kdl
+
 " Kixtart
 au BufNewFile,BufRead *.kix			setf kix
 

src/testdir/test_filetype.vim

@@ -300,6 +300,7 @@ let s:filename_checks = {
     \ 'jsp': ['file.jsp'],
     \ 'julia': ['file.jl'],
     \ 'kconfig': ['Kconfig', 'Kconfig.debug', 'Kconfig.file'],
+    \ 'kdl': ['file.kdl'],
     \ 'kivy': ['file.kv'],
     \ 'kix': ['file.kix'],
     \ 'kotlin': ['file.kt', 'file.ktm', 'file.kts'],

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1263,
 /**/
     1262,
 /**/