patch 9.1.2094: filetype: tiger files are not recognized

Problem:  filetype: tiger files are not recognized
Solution: Detect *.tig files as tiger filetype
          (Christian Clason).

Reference:
- https://www.cs.princeton.edu/~appel/modern/

closes: #19202

Signed-off-by: Christian Clason <c.clason@uni-graz.at>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/autoload/dist/ft.vim

@@ -2827,6 +2827,8 @@ const ft_from_ext = {
   "txi": "texinfo",
   # Thrift (Apache)
   "thrift": "thrift",
+  # Tiger
+  "tig": "tiger",
   # TLA+
   "tla": "tla",
   # TPP - Text Presentation Program

src/testdir/test_filetype.vim

@@ -886,6 +886,7 @@ def s:GetFilenameChecks(): dict<list<string>>
     tf: ['file.tf', '.tfrc', 'tfrc'],
     thrift: ['file.thrift'],
     tidy: ['.tidyrc', 'tidyrc', 'tidy.conf'],
+    tiger: ['file.tig'],
     tilde: ['file.t.html'],
     tla: ['file.tla'],
     tli: ['file.tli'],

src/version.c

@@ -734,6 +734,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2094,
 /**/
     2093,
 /**/