Add tests for print_emoji_detection_script function #1420

Job	Run time
Core running from build / Core running from build / Linux	2m 3s
Core running from src / Core running from src / Linux	2m 4s
Core running from build / Core running from build / Windows	3m 10s
Core running from src / Core running from src / Windows	3m 5s
Core running from build / Core running from build / MacOS	3m 51s
Core running from src / Core running from src / MacOS	5m 7s
Gutenberg running from build / Gutenberg running from build / Linux	8m 13s
Gutenberg running from src / Gutenberg running from src / Linux	8m 52s
Gutenberg running from build / Gutenberg running from build / Windows	11m 10s
Gutenberg running from src / Gutenberg running from src / Windows	11m 15s
Gutenberg running from build / Gutenberg running from build / MacOS	15m 13s
Gutenberg running from src / Gutenberg running from src / MacOS	16m 32s
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	1h 30m 39s

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