Slack API issues with deserializing api payloads

For one of our customers, we hit this deserialization issue with 1.45.2 of the sdk.

Got an exception while calling conversations.history API (team: ****, error: java.lang.IllegalStateException: Not a JSON Object: [])

j.l.IllegalStateException: Not a JSON Object: []
at c.g.gson.JsonElement.getAsJsonObject(JsonElement.java:165)
at c.s.a.u.j.GsonFileFactory.deserialize(GsonFileFactory.java:46)
at c.s.a.u.j.GsonFileFactory.deserialize(GsonFileFactory.java:8)
at c.g.g.i.b.TreeTypeAdapter.read(TreeTypeAdapter.java:95)
at c.g.g.i.b.ReflectiveTypeAdapterFactory$2.readIntoField(ReflectiveTypeAdapterFactory.java:267)
at c.g.g.i.b.ReflectiveTypeAdapterFactory$FieldReflectionAdapter.readField(ReflectiveTypeAdapterFactory.java:558)
at c.g.g.i.b.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:516)
... 40 common frames omitted
Wrapped by: c.g.g.JsonSyntaxException: java.lang.IllegalStateException: Not a JSON Object: []
at c.g.g.i.b.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:520)
at c.google.gson.Gson.fromJson(Gson.java:1361)
at c.google.gson.Gson.fromJson(Gson.java:1463)
at c.google.gson.Gson.fromJson(Gson.java:1434)
at c.g.g.i.b.TreeTypeAdapter$GsonContextImpl.deserialize(TreeTypeAdapter.java:199)
at c.s.a.u.j.GsonLayoutBlockFactory.deserialize(GsonLayoutBlockFactory.java:31)
at c.s.a.u.j.GsonLayoutBlockFactory.deserialize(GsonLayoutBlockFactory.java:12)
at c.g.g.i.b.TreeTypeAdapter.read(TreeTypeAdapter.java:95)
at c.g.g.i.b.TypeAdapterRuntimeTypeWrapper.read(TypeAdapterRuntimeTypeWrapper.java:40)
at c.g.g.i.b.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:83)
at c.g.g.i.b.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:59)
at c.g.g.i.b.ReflectiveTypeAdapterFactory$2.readIntoField(ReflectiveTypeAdapterFactory.java:267)
at c.g.g.i.b.ReflectiveTypeAdapterFactory$FieldReflectionAdapter.readField(ReflectiveTypeAdapterFactory.java:558)
at c.g.g.i.b.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:516)
at c.g.g.i.b.TypeAdapterRuntimeTypeWrapper.read(TypeAdapterRuntimeTypeWrapper.java:40)
at c.g.g.i.b.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:...

Start with GsonFileFactory.java at deserialize, then inspect GsonLayoutBlockFactory.java and the conversations.history payload involved in the stack trace. Reproduce the reported response and determine why an array reaches code expecting a JSON object; done means the payload deserializes without the reported exception and the relevant test coverage passes.