[UPGRADE] Deprecated beam runners direct package

[dcreey]

TL;DR

Error: t/data_migration_pipeline/main.go:31:2: SA1019: "github.com/apache/beam/sdks/v2/go/pkg/beam/runners/direct" is deprecated: Use prism as a local runner instead. Reliance on the direct runner leads to non-portable pipelines. (staticcheck)

[sethvargo]

@lock14 and I looked into doing this awhile back and it was impossible because of a transitive dependency issue. Perhaps that's since been addressed.