Promote TFP version from dev to stable

Update version and TF requirement for TFP 0.24.0 release.

Update version and TF version requirement for TFP 0.23.0 release.

Update version for TFP 0.22.1.

Drop Python 3.8 support for TFP 0.22 and later.

Update version and TF version requirement for TFP 0.21.0 release.

Update version and TF version requirement for TFP 0.20.0 release.

Merge pull request #1660 from emilyfertig/r0.19

Add deprecation notice to `log_cumsum_exp`.

When using TensorFlow, TFP 0.18 requires TF 2.10+.

Update version for the TFP 0.17.0 release.