enh(Poco::Dynamic): Modernised code to use C++17 features. #2782

Job	Run time
android-arm64-v8a-ndk-cmake	8m 25s
android-arm64-v8a-ndk-latest-cmake	8m 16s
android-armeabi-v7a-ndk-cmake	2m 18s
linux-gcc-make-armv7l	1m 52s
linux-gcc-make	21m 46s
linux-gcc-make-asan	29m 59s
linux-gcc-make-asan-no-soo	28m 33s
linux-gcc-make-cxx20	26m 44s
linux-gcc-make-trace	22m 16s
linux-gcc-make-ubsan	33m 1s
linux-emscripten-cmake	1m 28s
linux-gcc-cmake	20m 27s
linux-gcc-make-cross-armhf	2m 42s
linux-gcc-cmake-unbundled	17m 56s
linux-gcc-make-tsan	25m 3s
macos-clang-cmake-openssl3	1m 17s
macos-clang-cmake-openssl3-visibility-hidden	1m 30s
macos-clang-make	3m 43s
macos-clang-make-visibility-hidden	4m 7s
linux-gcc-make-mysql	8m 7s
linux-gcc-make-postgres	8m 48s
macos-clang-make-openssl3-asan	4m 16s
macos-clang-make-openssl3-tsan	2m 45s
macos-clang-make-openssl3-ubsan	6m 36s
windows-2022-msvc-buildwin-x64	3m 1s
windows-2022-msvc-cmake	3m 22s
windows-2022-msvc-cmake-static	3m 5s
windows-2022-msvc-cmake-static-mt	3m 1s
linux-gcc-make-mongodb	8m 24s
linux-gcc-make-odbc	15m 13s
linux-gcc-make-redis	9m 37s
linux-gcc-make-sqlite-no-sqlparser	8m 15s
	5h 45m 53s

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