Fix NavigationPolygon not updating consistently on rebakes #34790

Job	Run time
📊 Static checks / Code style, file formatting, and docs	1m 40s
🤖 Android / Editor (target=editor)	24m 27s
🤖 Android / Template arm32 (target=template_release, arch=arm32)	16m 31s
🤖 Android / Template arm64 (target=template_release, arch=arm64)	19m 16s
🐧 Linux / Editor w/ Mono (target=editor)	41m 18s
🐧 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)	48m 16s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	37m 13s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	31m 47s
🍏 iOS / Template (target=template_release)	9m 2s
🐧 Linux / Template w/ Mono (target=template_release)	25m 16s
🍎 macOS / Editor (target=editor, tests=yes)	26m 56s
🐧 Linux / Minimal template (target=template_release, everything disabled)	15m 24s
🌐 Web / Template w/ threads (target=template_release, threads=yes)	25m 39s
🍎 macOS / Template (target=template_release)	17m 43s
🌐 Web / Template w/o threads (target=template_release, threads=no)	25m 35s
🏁 Windows / Editor (target=editor, tests=yes)	48m 23s
🏁 Windows / Template (target=template_release)	34m 27s
🪲 Godot CPP / Build and test Godot CPP	7m 57s
	7h 36m 50s

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