Added balancers.PreferNearestDC[WithFallback] balancers + Marked as deprecated balancers.PreferLocalDC[WithFallback] balancers

[asmyasnikov]

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Other information

[github-actions]

github.com/ydb-platform/ydb-go-sdk/v3/balancers

compatible changes

PreferNearestDC: added
PreferNearestDCWithFallBack: added

summary

Base version: v3.80.1 (master)
Suggested version: v3.81.0

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 78.26087% with 5 lines in your changes missing coverage. Please review.

Project coverage is 67.65%. Comparing base (ab4aa77) to head (60f9297).

Files with missing lines	Patch %	Lines
balancers/balancers.go	58.33%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1450      +/-   ##
==========================================
- Coverage   67.75%   67.65%   -0.11%     
==========================================
  Files         349      349              
  Lines       36234    36249      +15     
==========================================
- Hits        24551    24524      -27     
- Misses      10600    10634      +34     
- Partials     1083     1091       +8     

Flag	Coverage Δ
experiment	71.69% <80.00%> (-0.37%)	⬇️
go-1.21.x	67.92% <78.26%> (-0.20%)	⬇️
go-1.22.x	65.47% <78.26%> (-0.24%)	⬇️
go-1.23.x	67.45% <78.26%> (-0.29%)	⬇️
integration	53.32% <15.00%> (-0.21%)	⬇️
macOS	40.96% <80.00%> (-0.04%)	⬇️
ubuntu	72.05% <80.00%> (-0.13%)	⬇️
unit	41.39% <78.26%> (-0.02%)	⬇️
windows	41.37% <78.26%> (-0.03%)	⬇️
ydb-23.3	47.61% <15.00%> (-0.33%)	⬇️
ydb-24.1	53.30% <15.00%> (-0.15%)	⬇️
ydb-nightly	71.69% <80.00%> (-0.37%)	⬇️

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[github-actions]

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[github-actions]

🌋 Here are results of SLO test for Native ydb-go-sdk/v3 over query-service:

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