patch 9.1.0278: filetype: zathurarc files not recognized

Problem:  filetype: zathurarc files not recognized
Solution: Detect '.zathurarc' files as zathurarc filetype,
          add zathurarc filetype (Wu, Zhenyu)

closes: #14380

Signed-off-by: Wu, Zhenyu <wuzhenyu@ustc.edu>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 03af297..3b94f96 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -827,6 +827,7 @@
     yang: ['file.yang'],
     yuck: ['file.yuck'],
     z8a: ['file.z8a'],
+    zathurarc: ['zathurarc'],
     zig: ['file.zig', 'build.zig.zon'],
     zimbu: ['file.zu'],
     zimbutempl: ['file.zut'],
diff --git a/src/version.c b/src/version.c
index 25b0399..93f6634 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    278,
+/**/
     277,
 /**/
     276,