cmCacheManager: Fix warning comment for cache vars containing newlines Reuse the logic from commit 637a0f7ed4 (cmCacheManager: Prevent corruption from multiline help strings, 2025-02-04, v4.0.0-rc1~52^2) for the warning message placed in the cache when a cache variable's value contains one or more newline characters. While we're at it, remove a superfluous early-exit in the help strings method. Fixes: #27807 Suggested-By: Yauheni Khnykin <yauheni.khnykin@here.com>