Drop unnecessary getattr(config, "key") calls

[mvdbeek]

They're always set, no point in doing this.

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[jmchilton]

There is a point to doing this - when code is used with alternative config objects by other libraries doing this simplifies the interface the library must produce for interacting with this code. I would push back in general but all of this seems to be from galaxy-app so I am not going to fight this but I do generally think there was a point. Especially the more useful libraries I think this made sense. For newer and more isolated code, I've switched to like local config objects with an adapter to Galaxy config object because you get stronger typing.

[mvdbeek]

Yep, agreed, I only looked for (variants of) app.config. The typing aspect is pretty important imo, we did have bugs in the past because of typos, which are harder to catch with getattr