[Telemetry] Add __repr__ to Error
[Telemetry] Add __repr__ to Error

There is at least one case in Telemetry where repr() is used on an Error
instead of just printing it out as a string. This results in all the
useful debug information included in the Error being discarded, which
defeats the entire purpose of the custom exception type. This adds a
__repr__ implementation to the class which is identical to the __str__
implementation.

Bug: chromium:1166310
Change-Id: I6457ffbf456dc019b6a406d91e0a0f52627ba1db
Reviewed-on: https://chromium-review.googlesource.com/c/catapult/+/2797547
Commit-Queue: Brian Sheedy <8cdc5cc1fa60ba15acb0d296e6f5592b7bb7d71c@chromium.org>
Commit-Queue: John Chen <334fbfbb4df7c78f091ea1b77c69ca6ac731a3f3@chromium.org>
Auto-Submit: Brian Sheedy <8cdc5cc1fa60ba15acb0d296e6f5592b7bb7d71c@chromium.org>
Reviewed-by: John Chen <334fbfbb4df7c78f091ea1b77c69ca6ac731a3f3@chromium.org>

catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult