Add full Emoji support to osu

[EYHN]

This feature is divided into three PRs.

• In osu (This PR)
• In osu-framework Add emoji support to SpriteText and TextBox osu-framework#6599
• In osu-resources Add noto color emoji osu-resources#369

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In this PR

• Add EmojiStore to load Emoji Textures resources
• Adapting to type changes from framework

BenchmarkEmojiStore Result:

Method	n	Mean	Error	StdDev	Gen0	Gen1	Gen2	Allocated
BenchmarkMissingEmoji	?	172.7 ns	2.09 ns	1.95 ns	0.0393	-	-	496 B
BenchmarkToGetResource	1	26,381.3 ns	509.04 ns	499.95 ns	5.8594	0.1221	-	74005 B
BenchmarkToGetResource	10	343,585.6 ns	6,248.93 ns	5,539.52 ns	58.5938	1.9531	-	741044 B
BenchmarkToGetResource	100	3,514,988.6 ns	62,320.43 ns	58,294.57 ns	593.7500	15.6250	3.9063	7410976 B