Prepare Groovy scripts for Kotlin DSL migration (#23355)

Summary:
Using Kotlin DSL in Gradle instead of Groovy will help detect problems early on using static typing, and it has advanced IDE support. This PR prepares Groovy script for Kotlin DSL migration per **Migrating build logic from Groovy to Kotlin** guide. Here is the excerpt:

>As a first migration step, it is recommended to prepare your Groovy build scripts by
> - unifying quotes using double quotes,
> - disambiguating function invocations and property assignments (using respectively parentheses and assignment operator).

See: https://guides.gradle.org/migrating-build-logic-from-groovy-to-kotlin/

[Android] [Changed] - Prepare Gradle scripts for Kotlin DSL migration
Pull Request resolved: #23355

Differential Revision: D14018504

Pulled By: mdvacca

fbshipit-source-id: 909982c715b640f102cbe723df578c9af7bae08e