feat: client could be configured via TOML file

[bednar]

Closes #201

Proposed Changes

Allow configuring client via TOML file - InfluxDB 2 config file.

Checklist

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

[codecov]

Codecov Report

Merging #203 (b0c5df5) into master (4f1e14e) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #203      +/-   ##
==========================================
+ Coverage   89.93%   89.94%   +0.01%     
==========================================
  Files          26       26              
  Lines        1967     1970       +3     
==========================================
+ Hits         1769     1772       +3     
  Misses        198      198              

Impacted Files	Coverage Δ
influxdb_client/client/influxdb_client.py	98.48% <100.00%> (+0.03%)	⬆️

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