Chore: Changelog for 2.0.3

Release: Changelog for 2.0.2

Fix: cursors get re-used when out of data

If we have reached the end of available data when paginating,
Obelisk returns a `null` cursor.
However, the library does not check for this case and keeps looping,
with said cursor set to null,
effectively duplicating the result set until the desired size is reached.

Improve CORE documentation

Merge pull request #11 from predict-idlab/10-prevent_infinite_retry

Fix infinite loop in retry logic

Merge pull request #7 from predict-idlab/fix_obelisk_precision

Fix: Obelisk TimestampPrecision as string

Merge pull request #7 from predict-idlab/fix_obelisk_precision

Fix: Obelisk TimestampPrecision as string

Add log error messages to ObeliskError as well

In things like notebooks, one cannot see the log output,
so errors are more useful.

Fix: get event loop instead of create

We used to create a new event loop in each sync instance,
which is silly and can error.

Fix sphinx build type