[RPM/CentOS7] Need to disable repo_gpgcheck on pgdg-common when using RPM version 42.0-17.1

Hello all,

This morning, a new RPM version has been sent to https://download.postgresql.org/pub/repos/yum/reporpms/EL-7-x86_64/ with version ID 42.0-17.1

We had to adapt our tooling to comply with this new repository file.

We faced the following error on section pgdg-common

> Failure talking to yum: failure: repodata/repomd.xml.asc from pgdg-common

Searching on the internet, we managed to perform a workaround disabling the parameter `repo_gpgcheck` into the section pgdg-common.

Hope it can help others,

Best regards,

Thomas