runtime(graphql): contribute vim-graphql to Vim core

Contribute the core of my vim-graphql project (ftplugin, indent, syntax)
to the Vim project. This replaces the basic ftplugin support that was
already in the runtime with a more complete set of filetype settings. I
can assume maintainership for all of these files.

I'll continue to maintain the higher-level embedded filetype support
separately (in vim-graphql) for now, because it's fairly complex, but we
can consider integrating that code directly into vim later.

runtime files use the MIT license.

closes: #16273

Signed-off-by: Jon Parise <jon@indelible.org>
Signed-off-by: Christian Brabandt <cb@256bit.org>

.github/MAINTAINERS

@@ -181,7 +181,7 @@ runtime/ftplugin/go.vim			@dbarnett
 runtime/ftplugin/goaccess.vim		@meonkeys
 runtime/ftplugin/gomod.vim		@yu-yk
 runtime/ftplugin/gprof.vim		@dpelle
-runtime/ftplugin/graphql.vim	@ribru17
+runtime/ftplugin/graphql.vim		@jparise
 runtime/ftplugin/gyp.vim		@ObserverOfTime
 runtime/ftplugin/haml.vim		@tpope
 runtime/ftplugin/hare.vim		@selenebun
@@ -339,6 +339,7 @@ runtime/indent/gitconfig.vim		@tpope
 runtime/indent/gitolite.vim		@sitaramc
 runtime/indent/glsl.vim		@gpanders
 runtime/indent/go.vim			@dbarnett
+runtime/indent/graphql.vim		@jparise
 runtime/indent/gyp.vim			@ObserverOfTime
 runtime/indent/haml.vim			@tpope
 runtime/indent/hare.vim			@selenebun
@@ -481,6 +482,7 @@ runtime/syntax/goaccess.vim		@meonkeys
 runtime/syntax/godoc.vim		@dbarnett
 runtime/syntax/gp.vim			@KBelabas
 runtime/syntax/gprof.vim		@dpelle
+runtime/syntax/graphql.vim		@jparise
 runtime/syntax/groff.vim		@jmarshall
 runtime/syntax/gyp.vim			@ObserverOfTime
 runtime/syntax/haml.vim			@tpope