docs(contributing): update guidelines
docs(contributing): update guidelines

[skip npm][skip ci] docs only

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