Add automatic external fetching for JSON and Googletest (#1253) #19

Job	Run time
build-ultralite / ultralite-windows	1m 0s
build-ultralite / ultralite-ubuntu	19s
build-fast / windows	51s
build-fast / focal-gcc-8	36s
build-fast / jammy-gcc-12	39s
doc / dev	1m 20s
doc / user	1m 18s
build-fast / focal-clang-10	43s
build-fast / jammy-clang-15	30s
all-prechecks	0s
build-spack	0s
build-docker	0s
all	4s
	7m 20s

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