docs(influxdb): add example for create operation

[magic-peach]

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Description

The InfluxDB binding page lists create and query as the two supported operations, but only query had a usage example. Added a ### Create section with a curl example, matching the measurement, tags, and values fields the component actually reads off the request data (verified against bindings/influx/influx.go in components-contrib, which builds an InfluxDB line protocol point from those three keys).

Issue reference

Please reference the issue this PR will close: #3279