lang/nodejs8: Update to 8.11.3.

- buffer (CVE-2018-7167): Fixes Denial of Service vulnerability where
  calling Buffer.fill() could hang
- http2:
  - (CVE-2018-7161): Fixes Denial of Service vulnerability by updating
    the http2 implementation to not crash under certain circumstances
    during cleanup
  - (CVE-2018-1000168): Fixes Denial of Service vulnerability by
    upgrading nghttp2 to 1.32.0

(fhajny)