fix: batch write

[rolincova]

Closes #

Briefly describe your proposed changes:

• CHANGELOG.md updated
• Rebased/mergeable
• Tests pass
• Sign CLA (if not already signed)

[codecov-io]

Codecov Report

Merging #22 into master will decrease coverage by 0.19%.
The diff coverage is 87.5%.

@@            Coverage Diff            @@
##           master      #22     +/-   ##
=========================================
- Coverage   99.18%   98.98%   -0.2%     
=========================================
  Files          10       10             
  Lines         488      491      +3     
=========================================
+ Hits          484      486      +2     
- Misses          4        5      +1

Impacted Files	Coverage Δ
lib/influxdb2/client/flux_csv_parser.rb	100% <100%> (ø)	⬆️
lib/influxdb2/client/worker.rb	90.47% <85.71%> (-2.03%)	⬇️

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