Add SECURITY.md #516

Job	Run time
copyright	3m 24s
build	6m 27s
shellcheck	3m 9s
checkstyle	4m 15s
spotbugs/core	10m 46s
tests/tck-cdi	17m 13s
tests/native-image-mp-1-linux	6m 48s
tests/core	11m 15s
spotbugs/integrations	7m 28s
tests/tck-rest	14m 52s
tests/native-image-mp-2-linux	12m 15s
tests/it	14m 32s
tests/tck-others	16m 50s
spotbugs/others	13m 35s
tests/native-image-mp-3-linux	6m 42s
tests/dbclient	9m 7s
tests/native-image-se-1-linux	6m 52s
tests/dbclient-oracle	17m 45s
tests/native-image-inject-linux	6m 38s
archetypes/r1-jar	6m 42s
tests/others	12m 15s
docs	4m 57s
archetypes/r2-jar	6m 57s
tests/native-image-mp-1-macos	10m 54s
archetypes/r3-jar	6m 8s
tests/native-image-mp-2-macos	18m 36s
examples/linux	12m 31s
archetypes/r4-jar	7m 10s
tests/native-image-mp-3-macos	12m 13s
javadoc (core)	6m 57s
examples/macos	10m 3s
archetypes/r5-jar	5m 37s
tests/native-image-se-1-macos	8m 24s
javadoc (integrations)	5m 20s
tests/native-image-inject-macos	6m 20s
javadoc (others)	7m 56s
archetypes/legacy	4m 36s
tests/packaging-jar-linux	7m 12s
quickstarts/linux	11m 40s
tests/packaging-jlink-linux	9m 43s
quickstarts/macos	15m 45s
tests/packaging-jar-macos	5m 58s
tests/packaging-jlink-macos	6m 56s
tests/results	12s
gate	1s
	6h 40m 56s

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