Replace Array.filter with Array.splice, to prevent the creation of a new...

... Array object. A new Array object might cause in-memory references to be lost, and potentially leak memory.

This should fix https://github.com/krakenjs/kraken-js/issues/285

All tests passed using `tap test/versioned/express*/*.tap.js` except one because it coudn't connect to some Redis instance I don't have installed.

A more complete explanation of this can be found here:
https://github.com/lmarkus/newrelicbuster