Add Sytest/Complement coverage to scheduled runs (#2962)

This adds Sytest and Complement coverage reporting to the nightly
scheduled CI runs.

Fixes a few API mode related issues as well, since we seemingly never
really ran them with Complement.

Also fixes a bug related to device list changes: When we pass in an
empty `newlyLeftRooms` slice, we got a list of all currently joined
rooms with the corresponding members. When we then got the
`newlyJoinedRooms`, we wouldn't update the `changed` slice, because we
already got the user from the `newlyLeftRooms` query. This is fixed by
simply ignoring empty `newlyLeftRooms`.

build/scripts/complement-cmd.sh

@@ -10,7 +10,7 @@ if [[ "${COVER}" -eq 1 ]]; then
     --tls-key server.key \
     --config dendrite.yaml \
     -api=${API:-0} \
-    --test.coverprofile=integrationcover.log
+    --test.coverprofile=complementcover.log
 else
   echo "Not running with coverage"
   exec /dendrite/dendrite-monolith-server \