ICU-22479 Add Fuzzer for DateFormat #808

Job	Run time
clang-valgrind-intltest (utility)	10m 16s
clang-valgrind-intltest (normalize)	7m 50s
clang-valgrind-intltest (collator)	6m 18s
clang-valgrind-intltest (regex)	7m 52s
clang-valgrind-intltest (format)	24m 7s
clang-valgrind-intltest (translit)	7m 36s
clang-valgrind-intltest (rbbi)	11m 3s
clang-valgrind-intltest (rbnf)	7m 55s
clang-valgrind-intltest (rbnfrt)	8m 35s
clang-valgrind-intltest (icuserv)	6m 19s
clang-valgrind-intltest (idna)	6m 18s
clang-valgrind-intltest (convert)	8m 35s
clang-valgrind-intltest (rbnfp)	7m 26s
clang-valgrind-test	17m 21s
clang-valgrind-intltest (csdet)	6m 14s
clang-valgrind-intltest (spoof)	6m 16s
clang-valgrind-intltest (bidi)	6m 46s
	2h 36m 47s

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