Disable XR server when compiling without 3D #25256

Job	Run time
📊 Static checks / Code style, file formatting, and docs	3m 44s
🍏 iOS / Template (target=template_release)	4m 59s
🐧 Linux / Editor w/ Mono (target=editor)	9m 14s
🐧 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)	21m 43s
🤖 Android / Template (target=template_release)	7m 11s
🍎 macOS / Editor (target=editor, tests=yes)	13m 24s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	9m 44s
🌐 Web / Template w/ threads (target=template_release, threads=yes)	6m 47s
🍎 macOS / Template (target=template_release)	6m 2s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	10m 28s
🌐 Web / Template w/o threads (target=template_release, threads=no)	6m 43s
🐧 Linux / Template w/ Mono (target=template_release)	5m 39s
🐧 Linux / Minimal template (target=template_release, everything disabled)	4m 24s
🏁 Windows / Editor (target=editor, tests=yes)	12m 38s
🏁 Windows / Template (target=template_release)	11m 29s
🪲 Godot CPP / Build and test Godot CPP	7m 0s
	2h 21m 9s

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