Add missing constraint to icu tests #4581

Job	Run time
msvc	10m 44s
gcc	12m 32s
msvc (CHECKS=nodep)	10m 50s
gcc (CFLAGS=-DTCL_NO_DEPRECATED=1)	12m 44s
msvc (OPTS=static)	11m 1s
gcc (--disable-shared)	12m 49s
msvc (OPTS=noembed)	10m 8s
gcc (--disable-zipfs)	12m 27s
msvc (OPTS=symbols)	10m 39s
gcc (--enable-symbols)	12m 50s
msvc (OPTS=symbols STATS=compdbg,memdbg)	14m 51s
gcc (--enable-symbols=mem)	14m 26s
gcc (--enable-symbols=all)	15m 36s
	2h 41m 37s

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