fix: initialization of the client without auth credentials

[bednar]

Closes #442

Proposed Changes

Fixed initialisation of the client without auth credentials:

from influxdb_client import InfluxDBClient

client = InfluxDBClient("localhost:8086")

Checklist

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

[codecov-commenter]

Codecov Report

Merging #443 (5e66a69) into master (1cad3f2) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head 5e66a69 differs from pull request most recent head 38d19ca. Consider uploading reports for the commit 38d19ca to get more accurate results

@@           Coverage Diff           @@
##           master     #443   +/-   ##
=======================================
  Coverage   89.32%   89.33%           
=======================================
  Files          38       38           
  Lines        3242     3243    +1     
=======================================
+ Hits         2896     2897    +1     
  Misses        346      346           

Impacted Files	Coverage Δ
influxdb_client/client/_base.py	98.13% <100.00%> (+<0.01%)	⬆️

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