Enable noUncheckedIndexedAccess for Tree

[RishhiB]

Enable noUncheckedIndexedAccess for Tree AB#8216

[msfluid-bot]

⯅ @fluid-example/bundle-size-tests: +2.5 KB

Metric Name	Baseline Size	Compare Size	Size Diff
aqueduct.js	457.46 KB	457.5 KB	⯅ +35 Bytes
azureClient.js	555.23 KB	555.28 KB	⯅ +49 Bytes
connectionState.js	680 Bytes	680 Bytes	■ No change
containerRuntime.js	258.67 KB	258.68 KB	⯅ +14 Bytes
fluidFramework.js	405.94 KB	407.08 KB	⯅ +1.14 KB
loader.js	134.04 KB	134.05 KB	⯅ +14 Bytes
map.js	42.13 KB	42.14 KB	⯅ +7 Bytes
matrix.js	145.61 KB	145.62 KB	⯅ +7 Bytes
odspClient.js	523.37 KB	523.42 KB	⯅ +49 Bytes
odspDriver.js	97.55 KB	97.57 KB	⯅ +21 Bytes
odspPrefetchSnapshot.js	42.61 KB	42.62 KB	⯅ +14 Bytes
sharedString.js	162.62 KB	162.63 KB	⯅ +7 Bytes
sharedTree.js	396.45 KB	397.59 KB	⯅ +1.14 KB
Total Size	3.3 MB	3.3 MB	⯅ +2.5 KB

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Baseline commit: 065417a9d356f03daed02ebf4281c5dadd055ceb

Generated by :no_entry_sign: dangerJS against b5879a32a78eceb573133895b503da975d8c0340