Added CI workflow to publish CVAT images

[azhavoro]

Motivation and context

resolve #7

How has this been tested?

Manually

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) 2021 Intel Corporation
#
# SPDX-License-Identifier: MIT

[coveralls]

Coverage increased (+0.02%) to 69.778% when pulling ad4d3ac on az/public_images into 9a56e7e on develop.

[nmanovic]

@azhavoro , don't forget to add news into CHANGELOG.md

[nmanovic]

Let's change comments for ffmpeg code and add info to CHANGELOG. Great job!

[nmanovic]

@azhavoro , also need to fix codacy issues.

[nmanovic]

@azhavoro , any updates?

[nmanovic]

Great job! I didn't test it, just reviewed the code. For me it looks fine.

[nmanovic]

@azhavoro , could you please notify all stakeholders about the achievement (gitter, Intel teams)? Need to clear emphasize why it is important (speed of the build, easy to deploy, alternative channel to distribute CVAT, etc).

[azhavoro]

@azhavoro , could you please notify all stakeholders about the achievement (gitter, Intel teams)? Need to clear emphasize why it is important (speed of the build, easy to deploy, alternative channel to distribute CVAT, etc).

Sure