patch 9.0.1182: go checksum files are not recognized

Problem:    go checksum files are not recognized.
Solution:   Add the name of go checksum files. (Amaan Qureshi, closes #11803)
diff --git a/runtime/filetype.vim b/runtime/filetype.vim
index ed2f63e..d199063 100644
--- a/runtime/filetype.vim
+++ b/runtime/filetype.vim
@@ -849,6 +849,9 @@
 " HCL
 au BufRead,BufNewFile *.hcl			setf hcl
 
+" Go checksum file (must be before *.sum Hercules)
+au BufNewFile,BufRead go.sum			setf gosum
+
 " Hercules
 au BufNewFile,BufRead *.vc,*.ev,*.sum,*.errsum	setf hercules
 
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 05ce070..d0cd3c5 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -230,6 +230,7 @@
     \ 'gnuplot': ['file.gpi', '.gnuplot'],
     \ 'go': ['file.go'],
     \ 'gomod': ['go.mod'],
+    \ 'gosum': ['go.sum'],
     \ 'gowork': ['go.work'],
     \ 'gp': ['file.gp', '.gprc'],
     \ 'gpg': ['/.gnupg/options', '/.gnupg/gpg.conf', '/usr/any/gnupg/options.skel', 'any/.gnupg/gpg.conf', 'any/.gnupg/options', 'any/usr/any/gnupg/options.skel'],
diff --git a/src/version.c b/src/version.c
index 898cc6b..b532948 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1182,
+/**/
     1181,
 /**/
     1180,