source-asana: don't cache Tasks records

A production task that only has the `Tasks` binding enabled is OOM-ing
because every `Tasks` record is being cached. I suspect this was done
because `Tasks` is used as a parent stream for some other streams. Not
caching `Tasks` records will likely slow down those other streams, but
right now no one is using those streams & we'd have to address these
OOMs due to caching regardless.

I also added some logging to give some indication that the connector is
doing something while the connector works on the full refresh `Tasks`
stream.

source-asana/source_asana/streams.py

@@ -179,10 +179,14 @@ class ProjectRelatedStream(AsanaStream, ABC):
     """
 
     def stream_slices(self, **kwargs) -> Iterable[Optional[Mapping[str, Any]]]:
-        yield from self.read_slices_from_records(
+        project_slices = self.read_slices_from_records(
             stream_class=Projects, slice_field="project_gid"
         )
 
+        for s in project_slices:
+            self.logger.info(f"Fetching {self.name} for project {s["project_gid"]}.")
+            yield s
+
 
 class AttachmentsCompact(AsanaStream):
     use_cache = True
@@ -480,8 +484,6 @@ def path(self, **kwargs) -> str:
 
 
 class Tasks(ProjectRelatedStream):
-    use_cache = True
-
     def path(self, **kwargs) -> str:
         return "tasks"