Formatting consistency: `arguments` vs `parameters`

[Blargian]

In the documentation for ClickHouse's aggregate functions we make a distinction between arguments and parameters (see for example exponentialMovingAverage) however for regular functions we use arguments in some cases and parameters in others.

For instance:

• log uses arguments
• sigmoid uses parameters

The usage of both is scattered around the docs. While the terms are probably interchangeable in this context I think we should be consistent in our formatting choices.

To do:

• [ ] decide on a convention.
• [ ] search through the docs and generate a list of all 'incorrect' usages.
• [ ] make the change to those functions.