docs(upgrading): add description to guide
docs(upgrading): add description to guide

aimeex3/spark-js-sdk,aimeex3/spark-js-sdk,mwegman/spark-js-sdk,bbender/spark-js-sdk,bbender/spark-js-sdk,adamweeks/spark-js-sdk,adamweeks/spark-js-sdk,mwegman/spark-js-sdk,adamweeks/spark-js-sdk,bbender/spark-js-sdk,aimeex3/spark-js-sdk,mwegman/spark-js-sdk