doc/gradle: grammatical edits to gradle language framework page (#467467)

  downstream, non-nixpkgs projects)

- `data` - path to the dependencies lockfile (can be relative to the

  package, can be absolute). In nixpkgs, it's discouraged to have the

  lockfiles be named anything other `deps.json`, consider creating

  lockfiles be named anything other than `deps.json`. Consider creating

  subdirectories if your package requires multiple `deps.json` files.

## Environment {#gradle-environment}