pyi is a python file too (ERT=1min)

[FrancescElies]

Adds pyi to python file types

[the-mikedavis]

This and few other extensions were added already in #5593:

helix/languages.toml

Lines 472 to 476 in 62d046f

	[[language]]
	name = "python"
	scope = "source.python"
	injection-regex = "python"
	file-types = ["py","pyi","py3","pyw","ptl",".pythonstartup",".pythonrc","SConstruct"]

[FrancescElies]

I had an old master, I should have pulled before creating a pr 😬