Bump version to 4.3.1-rc #18

Job	Run time
📊 Static checks / Code style, file formatting, and docs	1m 6s
🍎 macOS / Editor (target=editor, tests=yes)	30m 39s
🍎 macOS / Template (target=template_release)	21m 19s
🤖 Android / Editor (target=editor)	24m 53s
🤖 Android / Template arm32 (target=template_release, arch=arm32)	16m 43s
🍏 iOS / Template (target=template_release)	10m 9s
🌐 Web / Template w/ threads (target=template_release, threads=yes)	26m 28s
🤖 Android / Template arm64 (target=template_release, arch=arm64)	16m 46s
🐧 Linux / Editor w/ Mono (target=editor)	40m 7s
🌐 Web / Template w/o threads (target=template_release, threads=no)	26m 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)	45m 26s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	35m 31s
🏁 Windows / Editor (target=editor, tests=yes)	46m 43s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	30m 55s
🏁 Windows / Template (target=template_release)	35m 20s
🐧 Linux / Template w/ Mono (target=template_release)	27m 12s
🐧 Linux / Minimal template (target=template_release, everything disabled)	15m 37s
🪲 Godot CPP / Build and test Godot CPP	7m 54s
	7h 39m 4s

Provide feedback