Revert incorrect `Rect2.expand` description. #38

Job	Run time
📊 Static checks / Code style, file formatting, and docs	4m 42s
🤖 Android / Template (target=template_release)	49m 12s
🌐 Web / Template (target=template_release)	28m 28s
🍏 iOS / Template (target=template_release)	28m 3s
🐧 Linux / Editor w/ Mono (target=editor)	55m 37s
🐧 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)	1h 13m 59s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	50m 2s
🐧 Linux / Template w/ Mono (target=template_release)	38m 3s
🐧 Linux / Minimal template (target=template_release, everything disabled)	22m 21s
🍎 macOS / Editor (target=editor, tests=yes)	43m 58s
🍎 macOS / Template (target=template_release)	29m 31s
🏁 Windows / Editor (target=editor, tests=yes)	1h 42m 41s
🏁 Windows / Template (target=template_release)	56m 1s
🪲 Godot CPP / Build and test Godot CPP	11m 23s
	9h 54m 1s

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