Add parameters to the logging of callActivity

Currently when you start a function by:
`yield context.df.callActivity("FunctionName", parameter);`

you end up with a log in the Log Analytics of _Executing 'Functions.FunctionName_


but the _parameter_ is not registered under Properties.

How (and potentially where, if it's not the right repo) could we change it?

Start by tracing the callActivity entry point and the code that emits the “Executing 'Functions.FunctionName'” Log Analytics record. Determine whether this repository owns the logging behavior or another component does. Done means the activity parameter is included under the log record’s Properties without exposing sensitive data.

Written by the indexing model from the issue text.