Cypress. Update case_1. Added check label color.

[dvkruchinin]

Related on #4007

Motivation and context

Updating the test to check for label color collisions.
I wrote a small script to identify color collisions of labels with different names.

from cvat.apps.dataset_manager.formats.utils import get_label_color
import itertools

label_color = {}
dublicates = {}

lst = [''.join(x) for x in itertools.product('abcdifg', repeat=4)]
for i in lst:
    label_color[i] = get_label_color(i, label_color.keys())

for key, value in label_color.items():
    dublicates.setdefault(value, set()).add(key)

dubl = [values for key, values in dublicates.items() if len(values) > 1]

print(dubl)

As a result , I got the names of the labels:
adaf and adia
Which had the same color before the fix rgb(50, 182, 148).
Based on these data, the test has been redesigned.

How has this been tested?

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