Possibility to define filetypes as part of .sops.yaml

[schlichtanders]

Hi there, I would like to encrypt dockerconfigjson files, which why ever are not ending on .json.

Using the command line I can add the --input-type argument, but I couldn't find a corresponding option for .sops.yaml creation_rules.

It would be great to specify key "input_type" in there, so that sops can also handle such extra files seamlessly

[hiddeco]

Related to (and duplicate of) #982 #813. (We should eventually support this).