setup.py

context:

* we tried merging a bunch of upstream changes to get current with
  head of signald master
* but those changes caused widespread channel crashes (mostly around
  `NotFoundException`s) so we rolled back
* but in so doing, we orphaned an MR in our fork that cleaned up our
  catch blocks significantly. this MR restores those changes

tracks MR:

* team-friendo/signald-fork!19

pins our signald container to:

* REPO_URL "https://0xacab.org/team-friendo/signald-fork.git"
* BRANCH "master"
* COMMIT_HASH "e284165b58a9983abb0bf70bf83d9ecfef945369"
* LABEL verson="1.0.6"