Don't allow weaker return type in overriden method #27790

Job	Run time
📊 Static checks / Code style, file formatting, and docs	3m 37s
🐧 Linux / Editor w/ Mono (target=editor)	6m 33s
🍎 macOS / Editor (target=editor, tests=yes)	5m 59s
🤖 Android / Template (target=template_release)	4m 51s
🐧 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)	12m 52s
🍏 iOS / Template (target=template_release)	4m 50s
🍎 macOS / Template (target=template_release)	4m 20s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	6m 47s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	7m 47s
🌐 Web / Template w/ threads (target=template_release, threads=yes)	5m 0s
🐧 Linux / Template w/ Mono (target=template_release)	1m 51s
🏁 Windows / Editor (target=editor, tests=yes)	10m 23s
🌐 Web / Template w/o threads (target=template_release, threads=no)	4m 55s
🐧 Linux / Minimal template (target=template_release, everything disabled)	1m 16s
🏁 Windows / Template (target=template_release)	8m 3s
🪲 Godot CPP	0s
	1h 29m 4s

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