Revert `OpenXRHand` to its pre-`SkeletonModifier3D` state #27858

Job	Run time
📊 Static checks / Code style, file formatting, and docs	3m 21s
🍏 iOS / Template (target=template_release)	3m 10s
🏁 Windows / Editor (target=editor, tests=yes)	9m 38s
🍎 macOS / Editor (target=editor, tests=yes)	5m 2s
🏁 Windows / Template (target=template_release)	8m 56s
🤖 Android / Template (target=template_release)	4m 40s
🍎 macOS / Template (target=template_release)	3m 22s
🐧 Linux / Editor w/ Mono (target=editor)	5m 55s
🐧 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)	16m 58s
🌐 Web / Template w/ threads (target=template_release, threads=yes)	4m 28s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	18m 43s
🌐 Web / Template w/o threads (target=template_release, threads=no)	4m 34s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	7m 11s
🐧 Linux / Template w/ Mono (target=template_release)	1m 40s
🐧 Linux / Minimal template (target=template_release, everything disabled)	1m 59s
🪲 Godot CPP / Build and test Godot CPP	6m 53s
	1h 46m 30s

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