remove release infos for consolidation

[Siegfriedk]

We are aligning the information about releases into sig-release. This removes/minimalizes the infos and references the future source of truth.

fixes https://github.com/eclipse-tractusx/sig-release/issues/572

See:

• https://github.com/eclipse-tractusx/sig-release/pull/662
• https://github.com/eclipse-tractusx/eclipse-tractusx.github.io/pull/852