[Swift] Adds a way to store external data and use them directly within the ByteBuffer #6638

Job	Run time
Build Linux C++ (11, g++-13)	1m 45s
Build Linux C++ (11, clang++-18)	2m 2s
Build Android (on Linux)	3m 26s
Build .NET Windows	1m 27s
Build Linux C++ (14, g++-13)	1m 43s
Build Windows C++ (11)	3m 52s
Build .NET Windows (-p:UnsafeByteBuffer=true)	1m 22s
Build Linux C++ (14, clang++-18)	1m 59s
Build Windows C++ (14)	3m 49s
Check Generated Code (g++-13)	1m 24s
Build Linux C++ (17, g++-13)	2m 2s
Build Windows C++ (17)	4m 9s
Build Linux C++ (17, clang++-18)	2m 14s
Check Generated Code (clang++-18)	1m 15s
Build Windows C++ (20)	5m 16s
Build Linux C++ (20, g++-13)	2m 6s
Build Linux (g++-13)	1m 52s
Build Windows C++ (23)	5m 26s
Build Linux with -DFLATBUFFERS_NO_FILE_TESTS	2m 1s
Build Linux (clang++-18)	2m 27s
Build Linux with out-of-source build location	1m 14s
Build Linux C++ (20, clang++-18)	2m 25s
Build Mac (for Intel)	1m 54s
Build Mac (universal build)	4m 20s
Build Linux C++ (23, g++-13)	2m 7s
Build Windows 2019	3m 41s
Build Benchmarks (on Linux) (g++-13)	2m 50s
Check Generated Code on Windows	3m 57s
Build Java	21s
Build Kotlin Linux	3m 11s
Build Kotlin MacOS	6m 50s
Build Rust Linux	1m 57s
Build Dart	1m 9s
Build Go	1m 17s
Build Nim	1m 15s
Build PHP	55s
Build Python	56s
Build Rust Windows	1m 30s
Build Swift (5.8)	2m 24s
Build Swift Wasm	3m 37s
Build TS	1m 25s
Build Swift (5.9)	2m 20s
Build Swift (5.10)	2m 23s
release-digests	0s
provenance	0s
	1h 45m 35s

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