Compilation warnings in PF tutorials #2107

Job	Run time
build-ubuntu-dep-apt (ubuntu-20.04, /usr/bin/gcc-9, /usr/bin/g++-9, 98)	9m 4s
build-ubuntu-dep-apt (ubuntu-20.04, /usr/bin/gcc-9, /usr/bin/g++-9, 11)	29m 44s
build-ubuntu-dep-apt (ubuntu-20.04, /usr/bin/gcc-9, /usr/bin/g++-9, 17)	32m 29s
build-ubuntu-dep-apt (ubuntu-20.04, /usr/bin/gcc-10, /usr/bin/g++-10, 98)	7m 44s
build-ubuntu-dep-apt (ubuntu-20.04, /usr/bin/gcc-10, /usr/bin/g++-10, 11)	26m 46s
build-ubuntu-dep-apt (ubuntu-20.04, /usr/bin/gcc-10, /usr/bin/g++-10, 17)	29m 52s
build-ubuntu-dep-apt (ubuntu-20.04, /usr/bin/clang, /usr/bin/clang++, 98)	9m 4s
build-ubuntu-dep-apt (ubuntu-20.04, /usr/bin/clang, /usr/bin/clang++, 11)	33m 42s
build-ubuntu-dep-apt (ubuntu-20.04, /usr/bin/clang, /usr/bin/clang++, 17)	37m 17s
build-ubuntu-dep-apt (ubuntu-22.04, /usr/bin/gcc-9, /usr/bin/g++-9, 98)	7m 12s
build-ubuntu-dep-apt (ubuntu-22.04, /usr/bin/gcc-9, /usr/bin/g++-9, 11)	24m 51s
build-ubuntu-dep-apt (ubuntu-22.04, /usr/bin/gcc-9, /usr/bin/g++-9, 17)	28m 13s
build-ubuntu-dep-apt (ubuntu-22.04, /usr/bin/gcc-10, /usr/bin/g++-10, 98)	7m 31s
build-ubuntu-dep-apt (ubuntu-22.04, /usr/bin/gcc-10, /usr/bin/g++-10, 11)	25m 29s
build-ubuntu-dep-apt (ubuntu-22.04, /usr/bin/gcc-10, /usr/bin/g++-10, 17)	27m 54s
build-ubuntu-dep-apt (ubuntu-22.04, /usr/bin/clang, /usr/bin/clang++, 98)	9m 50s
build-ubuntu-dep-apt (ubuntu-22.04, /usr/bin/clang, /usr/bin/clang++, 11)	34m 0s
build-ubuntu-dep-apt (ubuntu-22.04, /usr/bin/clang, /usr/bin/clang++, 17)	37m 45s
	6h 58m 27s

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