Removed Cholesky from non-working section of release notes

Author: fonnesbeck

RELEASE-NOTES.md

@@ -14,7 +14,6 @@ Instead update the vNext section until 4.0.0 is out.
 We plan to get these working again, but at this point their inner workings have not been refactored.
 - Timeseries distributions (see [#4642](https://github.com/pymc-devs/pymc/issues/4642))
 - Mixture distributions (see [#4781](https://github.com/pymc-devs/pymc/issues/4781))
-- Cholesky distributions (see WIP PR [#4784](https://github.com/pymc-devs/pymc/pull/4784))
 - Variational inference submodule (see WIP PR [#4582](https://github.com/pymc-devs/pymc/pull/4582))
 - Elliptical slice sampling (see [#5137](https://github.com/pymc-devs/pymc/issues/5137))
 - `BaseStochasticGradient` (see [#5138](https://github.com/pymc-devs/pymc/issues/5138))