heex template highlighting breaks when there's a space at the end of an attribute

Hi everyone

I've tested this on a "raw" vim with only the vim-elixir plugin, to make sure that no other plugins are interfering.

The bug is that adding a single space at the end of an attribute breaks the highlighting, as can bee seen here (the closing div is the wrong color):

And this is what it should look like:

This is obviously not an issue for the given example, but I get the same error when I have more complicated attributes that embed some elixir code, like e.g.:

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