Actions Transforms should allow environment variables in query params

### Is your proposal related to a problem?

Many rest endpoints require sending a key in the query params. Defining this in multiple locations is not sustainable. There should be a way to provide an ENV variable as you can for the action_base_path

### Describe the solution you'd like

Choose an environment variable for the value of the query parameter.

### Describe alternatives you've considered

No alternative exists.

The issue does not name any files, tests, or entry points. Start by locating the Actions Transforms implementation and its configuration tests, then trace how action_base_path reads environment variables. Done means query-parameter values can be selected from environment variables and the behavior is covered by tests.

Written by the indexing model from the issue text.