[ti_misp] Update ECS to 8.4.0

[leehinman]

Update ti_misp to ECS 8.4.0

Closes #3890

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• Start Time: 2022-08-01T18:06:31.243+0000

• Duration: 15 min 46 sec

Test stats 🧪

Test	Results
Failed	0
Passed	9
Skipped	0
Total	9

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🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (1/1)	💚
Files	100.0% (1/1)	💚 3.175
Classes	100.0% (1/1)	💚 3.175
Methods	100.0% (14/14)	💚 11.293
Lines	88.475% (261/295)	👎 -0.838
Conditionals	100.0% (0/0)	💚

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