Fixed two issues #2053 and #2202

[bsekachev]

Motivation and context

1. Fixed use case when UI throws exception: Cannot read property 'objectType' of undefined (resolve UI exception: TypeError: Cannot read property 'objectType' of undefined #2053)
2. Fixed use case when logs could be saved twice or more times (resolve Sometimes logs can be sent twice #2202)

How has this been tested?

Manual testing

Checklist

• I submit my changes into the develop branch
• I have added description of my changes into CHANGELOG file
• I have updated the documentation accordingly
• I have added tests to cover my changes
• I have linked related issues (read github docs)
• I have increased versions of npm packages if it is necessary (cvat-canvas,
  cvat-core, cvat-data and cvat-ui)

License

• I submit my code changes under the same MIT License that covers the project.
  Feel free to contact the maintainers if that's a concern.
• I have updated the license header for each file (see an example below)

# Copyright (C) 2020 Intel Corporation
#
# SPDX-License-Identifier: MIT

[coveralls]

Coverage decreased (-0.03%) to 65.356% when pulling e84d244 on bs/fixed_two_issues into 8330015 on develop.