Create release notes for 5.8.x on 4.12, 4.13, 4.14, 4.15

Advisory link: https://errata.devel.redhat.com/advisory/146675, https://errata.devel.redhat.com/advisory/147196

Criteria = "Release Note Type" field is not empty and release note text provided. Jiras must be in the errata.

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If jiras do not contain release notes text, show the CVE's only. Example.