fix: add explicit dependency on rigetti-pyo3's "time" feature

In rigetti/rigetti-pyo3#45 (and rigetti/rigetti-pyo3#46), I moved all references to the Python time types under the "time" feature. This was a bugfix, but I didn't realize it was also a breaking change – any library that relied on the time types implicitly being available would break, just as this one did! This adds the missing feature dependency, and I've also upgraded rigetti/rigetti-pyo3#46 to be a breaking change.

This commit also updates Cargo.lock to force the update to rigetti-pyo3, meaning that builds will fail without the substantive change.

Closes #475.

rigetti / qcs-sdk-rust

fix: add explicit dependency on rigetti-pyo3's "time" feature #476