feat: add SecondsSinceEpochScalar#163

clutcher wants to merge 3 commits intographql-java:valueToLiteral_supportgraphql-java/graphql-java-extended-scalars:valueToLiteral_supportfrom

clutcher:seconds_since_epoch_scalarclutcher/graphql-java-extended-scalars:seconds_since_epoch_scalarCopy head branch name to clipboard