[RPM] obscure signature in jdk temurin subpkg

[andrlos]

Hi, so for all three versions of jdk rpm packages there is an extra signature on jdk packages.
Look for yourself with: rpm -K --verbose rpmFileName
example outputs:
rpms/temurin-11-jdk-11.0.18.0.0.10-2.x86_64.rpm:
Header V4 RSA/SHA256 Signature, key ID 65f8f04b: NOKEY
Header SHA256 digest: OK
Header SHA1 digest: OK
Payload SHA256 digest: OK
MD5 digest: OK

rpms/temurin-11-jre-11.0.18.0.0.10-2.x86_64.rpm:
Header SHA256 digest: OK
Header SHA1 digest: OK
Payload SHA256 digest: OK
MD5 digest: OK

My issues are all connected to the first line in the jdk package output:

1. I keep getting me warnings about missing key when analyzing the rpm.
2. why is the signature even there? is that a legacy obsolete forgotten piece of code or an attempt of something new? There is no such thing with ojdk rpms