PR#25899 added anstd::terminate() call without a corresponding include for<exception>:

This can cause a compilation error if the header is not coincidentally included elsewhere, as encountered here:conan-io/conan-center-index#27787

modules/core/src/system.cpp:1321:10: error: no member named 'terminate' in namespace 'std' 1321 |     std::terminate();      |     ~~~~~^

Pull Request Readiness Checklist

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• I agree to contribute to the project under Apache 2 License.
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  Patch to opencv_extra has the same branch name.
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