content: Add exhibit with `BecomeBlinker` block. #309

Job	Run time
miri	1m 31s
no_std	27s
build (ubuntu, stable, locked, true)	13m 18s
build (windows, stable, locked, false)	23m 48s
build (macos, stable, locked, false)	9m 32s
build (ubuntu, nightly, locked, false)	20m 5s
build (ubuntu, beta, locked, false)	19m 41s
build (ubuntu, stable, latest, false)	11m 45s
build (ubuntu, stable, minimal, false)	12m 30s
deploy	5s
features	23m 42s
fuzz	15m 6s
	2h 31m 30s

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