runtime(elixir): fix indentation (#13771)

Signed-off-by: George Guimarães <george.guimaraes@gmail.com>
Signed-off-by: Mitchell Hanberg <mitch@mitchellhanberg.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

Author: georgeguimaraes

runtime/ftplugin/elixir.vim

@@ -1,7 +1,7 @@
 " Elixir filetype plugin
 " Language: Elixir
 " Maintainer:	Mitchell Hanberg <vimNOSPAM@mitchellhanberg.com>
-" Last Change: 2022 Sep 20
+" Last Change: 2023 Dec 26
 
 if exists("b:did_ftplugin")
   finish
@@ -27,6 +27,12 @@ setlocal shiftwidth=2 softtabstop=2 expandtab iskeyword+=!,?
 setlocal comments=:#
 setlocal commentstring=#\ %s
 
+setlocal indentkeys=0#,!^F,o,O
+" Enable keys for blocks
+setlocal indentkeys+=0=after,0=catch,0=do,0=else,0=end,0=rescue
+" Enable keys that are usually the first keys in a line
+setlocal indentkeys+=0->,0\|>,0},0],0),>
+
 let b:undo_ftplugin = 'setlocal sw< sts< et< isk< com< cms<'
 
 let &cpo = s:save_cpo