Add a vector store driver for DataStax Astra DB

[hemidactylus]

• I have read and agree to the contributing guidelines.

Is your feature request related to a problem? Please describe.

DataStax' "Astra DB" database has first-class vector/ANN support and it would be desirable to have a vector store driver to enable using that backend from Griptape.

Describe the solution you'd like

Implementation of an AstraDBVectorStoreDriver subclass of BaseVectorStoreDriver.

Describe alternatives you've considered

n/a

Additional context

I can provide the implementation.