n-api,test: add int64 bounds tests

Added some simple tests to verify that the int64 API is correctly
handling numbers greater than 32-bits. This is a basic test, but
verifies that an implementer hasn't truncated back to 32-bits.

Refs: https://github.com/nodejs/node-chakracore/pull/496

PR-URL: https://github.com/nodejs/node/pull/19309


Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gabriel Schulhof <gabriel.schulhof@intel.com>
Reviewed-By: James M Snell <jasnell@gmail.com>