Add some additional coverage for strict mode/internal keywords #8710

Job	Run time
Debug and Prebuilt (All Tests by Package + Canary Features)	3m 42s
Type Checking (current version)	41s
Linting	1m 10s
Type Checking (other supported versions) (4.9)	59s
Type Checking (other supported versions) (5.0)	58s
Type Checking (other supported versions) (5.1)	55s
Type Checking (other supported versions) (5.2)	1m 7s
Type Checking (other supported versions) (5.3)	58s
Blueprint Tests	7m 55s
Browserstack Tests (Safari, Edge)	2m 18s
Debug and Prebuilt (All Tests by Package + Canary Features) with all Deprecations enabled	3m 4s
Debug and Prebuilt (All Tests by Package + Canary Features) with Deprecations as Errors	3m 15s
Production (All Tests + Canary Features with Debug Render Tree)	2m 57s
Production (All Tests + Canary Features)	3m 21s
Smoke tests (Full Ember Apps)	1m 19s
Browser Tests (Firefox)	2m 5s
Extend Prototypes	2m 39s
Node.js Tests	54s
Deploy tags to npm	0s
Publish channel to s3	0s
Publish alpha from default branch	0s
Notify Discord	0s
	40m 17s

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