chore(kernel): use ES private fields #8400

Job	Run time
Build	8m 27s
Create Release Package	8m 21s
Integration test (jsii-pacmak)	45m 33s
Run benchmark suite	54m 51s
Test (baseline)	23m 15s
Test (Windows)	43m 4s
Test (macOS)	40m 23s
Test (Node 16)	28m 38s
Test (Node 18)	30m 53s
Test (Node 20)	23m 57s
Test (.NET 7.0)	26m 28s
Test (Go 1.19)	24m 38s
Test (Java 11)	24m 53s
Test (Python 3.8)	25m 39s
Test (Python 3.9)	25m 0s
Test (Python 3.10)	24m 31s
Test (Python 3.11)	24m 39s
Unit Tests	2s
	8h 3m 12s

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