Boxsdk

- Fixing an issue in v2.3.0 where package could not be installed.

- Added the ability to set [file description upon
upload](https://github.com/box/box-python-sdk/blob/main/docs/usage/files.md#upload-a-file)
- Added support for [basic authenticated proxy and unauthenticated
proxy](https://github.com/box/box-python-sdk/blob/main/docs/usage/configuration.md#proxy)

- Updated requests-toolbelt dependency restriction.

- Fixing an issue in v2.2.0 where package could not be installed.

- Added abilty for user to [retrieve an
avatar](https://github.com/box/box-python-sdk/blob/main/docs/usage/user.md#get-the-avatar-for-a-user)
for a user.
- Changed retry strategy to use exponential backoff with randomized
jitter.

- Added ability for user to [chunk upload
files](https://github.com/box/box-python-sdk/blob/main/docs/usage/files.md#chunked-upload)
and resume uploads for interrupted uploads.
- Added ability to [verify webhook
message](https://github.com/box/box-python-sdk/blob/main/docs/usage/webhook.md#validate-webhook-message).
- Added ability for user to add metadata classification to
[files](https://github.com/box/box-python-sdk/blob/main/docs/usage/files.md#set-a-classification)
and
[folders](https://github.com/box/box-python-sdk/blob/main/docs/usage/folders.md#set-a-classification).
- Bugfix where calling `.response_object()` method on an API object
could throw.