Backup health check broken when using S3

ERROR 2021-12-01 22:39:35,801 backends: Unexpected Error!
Traceback (most recent call last):
File "/usr/local/lib/python3.9/dist-packages/health_check/backends.py", line 30, in run_check
self.check_status()
File "/usr/local/lib/python3.9/dist-packages/aleksis/core/health_checks.py", line 37, in check_status
if not storage.storage.exists(""):
File "/usr/local/lib/python3.9/dist-packages/storages/backends/s3boto3.py", line 469, in exists
self.connection.meta.client.head_object(Bucket=self.bucket_name, Key=name)
File "/usr/local/lib/python3.9/dist-packages/botocore/client.py", line 391, in _api_call
return self._make_api_call(operation_name, kwargs)
File "/usr/local/lib/python3.9/dist-packages/botocore/client.py", line 691, in _make_api_call
request_dict = self._convert_to_request_dict(
File "/usr/local/lib/python3.9/dist-packages/botocore/client.py", line 739, in _convert_to_request_dict
request_dict = self._serializer.serialize_to_request(
File "/usr/local/lib/python3.9/dist-packages/botocore/validate.py", line 360, in serialize_to_request
raise ParamValidationError(report=report.generate_report())
botocore.exceptions.ParamValidationError: Parameter validation failed:
Invalid length for parameter Key, value: 0, valid min length: 1

added prio::1 type::bug labels

assigned to @nik

created merge request !800 (merged) to address this issue

mentioned in merge request !800 (merged)

closed with merge request !800 (merged)

mentioned in commit d65522ed