Remove a stray Q_REQUIRED_RESULT
- The method in KCalFormat that this function is overriding doesn't have Q_REQUIRED_RESULT
- Setting Q_REQUIRED_RESULT on a function returning a bool isn't that useful IMHO
And it was making the build fail on the CI, Q_REQUIRED_RESULT which expands to [[nodiscard]] must be the first thing on the line.
GIT_SILENT