[pkg/ottl] Replace instances of "query" with "statement"

[evan-bradley]

Description:

This replaces the remaining instances of "query" with "statement" between the OTTL and transform processor. For simplicity, I've made this a breaking change in both components. We could make the change more gradual by supporting both queries and statements, but that would require additional logic to process both and handle precedence, so it seems like a better move to take advantage of the alpha status of the transform processor here.

Testing:

Unit tests have been updated and run, and the changes were run locally.

Documentation:

Updated relevant READMEs.

[TylerHelmuth]

thanks for taking this

[kovrus]

lgtm

[splunkenizer]

Should the docu here be changed to statements as well? https://github.com/open-telemetry/opentelemetry-collector/blob/main/docs/processing.md#telemetry-query-language