Bug Fixes
1. [672](https://github.com/influxdata/influxdb-client-python/pull/672): Adding type validation to url attribute in client object
2. [674](https://github.com/influxdata/influxdb-client-python/pull/674): Add type linting to client.flux_table.FluxTable, remove duplicated `from pathlib import Path` at setup.py
3. [675](https://github.com/influxdata/influxdb-client-python/pull/675): Ensures WritePrecision in Point is preferred to `DEFAULT_PRECISION`