Remove overwrite for phenotype region endpoint documentation
Remove overwrite for phenotype region endpoint documentation

This should be merged into master once the following pull request is merged into
the master branch of ensembl-rest:
https://github.com/Ensembl/ensembl-rest/pull/199

Related to ENSEMBL-4883.

EnsemblGenomes/eg-rest,EnsemblGenomes/eg-rest