Added more info to output during ui build

[bsekachev]

Motivation and context

Related #1862

How has this been tested?

Tried to build

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

Docker cannot display npm progress bar
One more option is to display some messages about installation (implemented)
https://stackoverflow.com/questions/49116606/docker-watch-logs-in-real-time-while-building-image/49117182

[coveralls]

Pull Request Test Coverage Report for Build 7101

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 3 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.01%) to 69.694%

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Files with Coverage Reduction	New Missed Lines	%
cvat/apps/engine/media_extractors.py	3	75.22%

Totals
Change from base Build 7097:	-0.01%
Covered Lines:	11742
Relevant Lines:	16392

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💛 - Coveralls

[nmanovic]

@bsekachev , @azhavoro , better to revert the change.