Frameworks KF6: drop no longer needed EXCLUDE_DEPRECATED_BEFORE_AND_AT arg
Any KF module is already setting any default version as needed. Usually 0, though KWallet has still some old API yet to be cut out, thus higher temporary version: See https://invent.kde.org/frameworks/kwallet/-/blob/master/CMakeLists.txt#L36
External API users relying on the resulting minimum versions effective in the macros *_BUILD_DEPRECATED_SINCE & *_ENABLE_DEPRECATED_SINCE should all have been ported meanwhile to use library versions instead, as they should be in control usually of the deprecated API actually used.
At least I could only find one remaining usage of the deprecation macros by consumers via lxr.kde.org, for which I just did a MR: multimedia/kdenlive!410 (merged)
Would there be anything else left that lxr failed to show (searched by using "foo/" in the file filter, using the groups like "graphics/", "education/", etc.).