chore: add container to vim syntax (#1533)

* Update snakemake.vim

Add `container` to list of directives for syntax highlighting.

* chore: add container to vim syntax

Split to multiple lines so I can pass the title check

* chore: add default_target and template_engine keywords

Co-authored-by: Johannes Köster <johannes.koester@tu-dortmund.de>
Co-authored-by: Johannes Köster <johannes.koester@uni-due.de>

misc/vim/syntax/snakemake.vim

@@ -47,8 +47,10 @@ source $VIMRUNTIME/indent/python.vim
 syn keyword pythonStatement include workdir onsuccess onerror onstart
 syn keyword pythonStatement ruleorder localrules configfile group 
 syn keyword pythonStatement wrapper conda shadow
-syn keyword pythonStatement input output params wildcards priority message threads resources singularity wildcard_constraints
+syn keyword pythonStatement input output params wildcards priority message
+syn keyword pythonStatement threads resources singularity container wildcard_constraints
 syn keyword pythonStatement version run shell benchmark snakefile log script
+syn keyword pythonStatement default_target template_engine
 syn keyword pythonStatement rule subworkflow checkpoint nextgroup=pythonFunction skipwhite
 syn keyword pythonBuiltinObj config checkpoints rules
 syn keyword pythonBuiltinFunc directory ancient pipe unpack expand temp touch protected