Fix TileMap::move_layer incorrectly moving child TileMapLayer nodes #119

Job	Run time
📊 Static checks / Code style, file formatting, and docs	2m 43s
🍏 iOS / Template (target=template_release)	15m 28s
🍎 macOS / Editor (target=editor, tests=yes)	33m 40s
🍎 macOS / Template (target=template_release)	14m 51s
🤖 Android / Template (target=template_release)	28m 36s
🌐 Web / Template w/ threads (target=template_release, threads=yes)	21m 34s
🐧 Linux / Editor w/ Mono (target=editor)	35m 17s
🏁 Windows / Editor (target=editor, tests=yes)	44m 28s
🐧 Linux / Editor with doubles and GCC sanitizers (target=editor, tests=yes, dev_build=yes, scu_build=yes, precision=double, use_asan=yes, use_ubsan=yes, linker=gold)	36m 49s
🏁 Windows / Template (target=template_release)	30m 53s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	32m 22s
🌐 Web / Template w/o threads (target=template_release, threads=no)	22m 7s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	6m 3s
🐧 Linux / Template w/ Mono (target=template_release)	1m 44s
🐧 Linux / Minimal template (target=template_release, everything disabled)	2m 10s
🪲 Godot CPP / Build and test Godot CPP	6m 47s
	5h 35m 32s

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