Clarify emitting behavior of GPU particles #24818

Job	Run time
📊 Static checks / Code style, file formatting, and docs	4m 6s
🤖 Android / Template (target=template_release)	4m 16s
🍏 iOS / Template (target=template_release)	2m 19s
🌐 Web / Template w/ threads (target=template_release, threads=yes)	4m 35s
🐧 Linux / Editor w/ Mono (target=editor)	5m 41s
🌐 Web / Template w/o threads (target=template_release, threads=no)	4m 16s
🐧 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 46s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	5m 49s
🍎 macOS / Editor (target=editor, tests=yes)	5m 0s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	7m 26s
🍎 macOS / Template (target=template_release)	2m 49s
🏁 Windows / Editor (target=editor, tests=yes)	9m 10s
🐧 Linux / Template w/ Mono (target=template_release)	2m 38s
🏁 Windows / Template (target=template_release)	8m 36s
🐧 Linux / Minimal template (target=template_release, everything disabled)	1m 16s
🪲 Godot CPP / Build and test Godot CPP	6m 59s
	1h 31m 42s

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