Refactoring: Add new constant Models.Commit.EmptyTreeSHA1 #2915

Job	Run time
Build / Build macOS (Intel)	3m 16s
Prepare version string	3s
Build / Build Linux (arm64)	2m 58s
Build / Build Windows ARM64	3m 43s
Build / Build Windows x64	3m 26s
Build / Build macOS (Apple Silicon)	2m 7s
Build / Build Linux	2m 44s
Package / Package macOS (osx-arm64)	16s
Package / Package Linux (linux-arm64)	59s
Package / Package Windows (win-arm64)	20s
Package / Package macOS (osx-x64)	16s
Package / Package Linux (linux-x64)	53s
Package / Package Windows (win-x64)	22s
	21m 23s

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