patch 9.0.1256: NetworkManager connection files are not recognized

Problem:    NetworkManager connection files are not recognized.
Solution:   Add a pattern for NetworkManager connection files. (closes #11893)

Author: ObserverOfTime

runtime/filetype.vim

@@ -1399,6 +1399,7 @@ au BufNewFile,BufRead pf.conf				setf pf
 " ini style config files, using # comments
 au BufNewFile,BufRead */etc/pacman.conf,mpv.conf	setf confini
 au BufNewFile,BufRead */.aws/config,*/.aws/credentials	setf confini
+au BufNewFile,BufRead *.nmconnection			setf confini
 
 " Pacman hooks
 au BufNewFile,BufRead *.hook

src/testdir/test_filetype.vim

@@ -121,7 +121,7 @@ let s:filename_checks = {
     \ 'conaryrecipe': ['file.recipe'],
     \ 'conf': ['auto.master'],
     \ 'config': ['configure.in', 'configure.ac', '/etc/hostname.file', 'any/etc/hostname.file'],
-    \ 'confini': ['/etc/pacman.conf', 'any/etc/pacman.conf', 'mpv.conf', 'any/.aws/config', 'any/.aws/credentials'],
+    \ 'confini': ['/etc/pacman.conf', 'any/etc/pacman.conf', 'mpv.conf', 'any/.aws/config', 'any/.aws/credentials', 'file.nmconnection'],
     \ 'context': ['tex/context/any/file.tex', 'file.mkii', 'file.mkiv', 'file.mkvi', 'file.mkxl', 'file.mklx'],
     \ 'cook': ['file.cook'],
     \ 'cpp': ['file.cxx', 'file.c++', 'file.hh', 'file.hxx', 'file.hpp', 'file.ipp', 'file.moc', 'file.tcc', 'file.inl', 'file.tlh'],

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1256,
 /**/
     1255,
 /**/