[now dev] Use empty version string for `@now/static` (#2159)
[now dev] Use empty version string for `@now/static` (#2159)

This is just a cosmetic fix so that "vbuilt-in" isn't printed when
`--debug` is enabled.
zeit/now-cli,zeit/now-cli,zeit/now-cli,zeit/now-cli,zeit/now-cli,zeit/now-cli,zeit/now-cli