improve russian translations

[Ashot-KR]

Improves some russian translations for admin UI:
fix some wrong translations
make some translations more "native"
add absent translations

[codecov]

Codecov Report

Merging #6903 into master will decrease coverage by 7.11%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #6903      +/-   ##
==========================================
- Coverage   27.16%   20.05%   -7.12%     
==========================================
  Files        1163      858     -305     
  Lines       15518    12049    -3469     
  Branches     2410     1950     -460     
==========================================
- Hits         4216     2416    -1800     
+ Misses       9534     8063    -1471     
+ Partials     1768     1570     -198     

Flag	Coverage Δ
#front	14.67% <ø> (-4.65%)	⬇️
#unit	42.45% <ø> (-11.41%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...t-manager/admin/src/containers/EditView/reducer.js	0.00% <0.00%> (-100.00%)	⬇️
...manager/admin/src/containers/ListView/constants.js	0.00% <0.00%> (-100.00%)	⬇️
packages/strapi-utils/lib/sanitize-entity.js	5.55% <0.00%> (-94.45%)	⬇️
...t-manager/admin/src/containers/ListView/reducer.js	0.00% <0.00%> (-93.34%)	⬇️
...t-manager/admin/src/containers/ListView/actions.js	0.00% <0.00%> (-90.91%)	⬇️
...api-admin/admin/src/containers/AuthPage/reducer.js	0.00% <0.00%> (-85.72%)	⬇️
packages/strapi-utils/lib/config.js	13.51% <0.00%> (-51.36%)	⬇️
...strapi-admin/admin/src/containers/Admin/actions.js	50.00% <0.00%> (-50.00%)	⬇️
...strapi-admin/admin/src/containers/Admin/reducer.js	80.00% <0.00%> (-20.00%)	⬇️
packages/strapi-utils/lib/validators.js	88.88% <0.00%> (-6.95%)	⬇️
... and 661 more

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[alexandrebodin]

Hi @Ashot-KR Would you mind fixing the conflicts ;)

[Ashot-KR]

@alexandrebodin sure, i'll do it later today

[reslear]

@Ashot-KR @alexandrebodin also look please another Russian language problem #7098 (Russian cyrillic ERROR on save - Content Type) Russian users really need. thx!

[Ashot-KR]

@reslear i got this error once 😄 actually pluralization in Russian not very easy thing. I will take a look and probably suggest some potential solutions

[Ashot-KR]

@alexandrebodin conflict resolved

[soupette]

LGTM