Merge adjacent string literals

[maffoo]

As a follow-up to the switch to using black for formatting with increased line length, this merges adjacent string literals that now fit on one line. (Thanks @dabacon for noticing this: #3516 (comment)).

[95-martin-orion]

Is this formatting change captured by the fmt-black tag, or should we merge a different tag to pick it up?

[maffoo]

@95-martin-orion, the fmt-black tag only includes the changes to the formatting script, but no actual formatting changes. If you have changes on an in-progress PR where you've modified files that are changed here, you'd get a merge conflict when merging master in the procedure outlined in #3516 (comment). Those conflicts would have to be fixed like any other conflicts when merging master.

[95-martin-orion]

Ah. I misunderstood this change as an update to the auto-formatting behavior, but I guess that behavior isn't really necessary outside of handling the recent line-width change. SGTM.

[maffoo]

Sorry, I should have clarified that this was just me search-and-replacing things like ' ' and ' f' in string literals, not a change to the formatter itself.

[95-martin-orion]

A couple cases look a bit strange at first glance (mostly assert conditions being split to multiple lines) but it's all formatted correctly. LGTM