feat: batching write - exponential random backoff

[rhajek]

Proposed Changes

Improves exponential random retry strategy in write api like in python client influxdata/influxdb-client-python#225

Delay is computed using random exponential backoff as a random value within the interval retryInterval * exponentialBase^(attempts-1) and retryInterval * exponentialBase^(attempts).

Example for retryInterval=5_000, exponentialBase=2, maxRetryDelay=125_000, total=5

Retry delays are random distributed values within the ranges of [5_000-10_000, 10_000-20_000, 20_000-40_000, 40_000-80_000, 80_000-125_000]

Checklist

• CHANGELOG.md updated
• Rebased/mergeable
• A test has been added if appropriate
• rake test completes successfully
• Commit messages are in semantic format
• Sign CLA (if not already signed)

[codecov-commenter]

Codecov Report

Merging #83 (897a072) into master (b9ef186) will decrease coverage by 0.34%.
The diff coverage is 95.00%.

@@            Coverage Diff             @@
##           master      #83      +/-   ##
==========================================
- Coverage   99.32%   98.98%   -0.35%     
==========================================
  Files          15       16       +1     
  Lines         742      785      +43     
==========================================
+ Hits          737      777      +40     
- Misses          5        8       +3     

Impacted Files	Coverage Δ
lib/influxdb2/client/write_retry.rb	94.00% <94.00%> (ø)
lib/influxdb-client.rb	100.00% <100.00%> (ø)
lib/influxdb2/client/worker.rb	92.72% <100.00%> (-1.12%)	⬇️
lib/influxdb2/client/write_api.rb	100.00% <100.00%> (ø)

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