Why does yum installation of rh-eclipse47-devstudio-11.3-0.20180413.0814.el7.x86_64 fail with gpgcheck error?

Issue

• Why does yum installation of rh-eclipse47-devstudio-11.3-0.20180413.0814.el7.x86_64 fail with gpgcheck error?

[root@rhel7test ~]# yum install rh-eclipse47-devstudio-11.3-0.20180413.0814.el7.x86_64
Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager
Resolving Dependencies
--> Running transaction check
---> Package rh-eclipse47-devstudio.x86_64 0:11.3-0.20180413.0814.el7 will be installed


Transaction Summary
================================================================================================
Install  1 Package (+300 Dependent packages)

Total size: 649 M
Installed size: 849 M
Is this ok [y/d/N]: y
Downloading packages:
warning: /var/cache/yum/x86_64/7Server/rhel-7-server-devtools-rpms/packages/rh-eclipse47-devstudio-11.3-0.20180413.0814.el7.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID a5787476: NOKEY
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release