node-api: factor out common code into macros

    * Create macro for checking new string arguments.
    * Create macro for combining env check and inside-gc check.

PR-URL: #50664
Reviewed-By: Vladimir Morozov <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Chengzhong Wu <[email protected]>
Backport-PR-URL: #51804
(cherry picked from commit 5e250bd)

Author: gabrielschulhof