Update test runner

test/run

 #!/bin/bash
 
-VIMRC=$TMPDIR/mini-vimrc
-SOURCE=$(dirname $BASH_SOURCE)/..
+cd $(dirname $BASH_SOURCE)
 
-cat > $VIMRC << EOF
-set nocompatible
+vim -Nu <(cat << EOF
 syntax on
-
 for dep in ['vader.vim', 'vim-repeat']
   execute 'set rtp+=' . finddir(dep, expand('~/.vim').'/**')
 endfor
-set rtp+=$SOURCE
-EOF
-
-vim -u $VIMRC +Vader*
-
-rm -f $VIMRC
+set rtp+=..
+EOF) +Vader*