Improve error message in text resource format parser #19

Job	Run time
📊 Static checks / Code style, file formatting, and docs	3m 10s
🍎 macOS / Editor (target=editor, tests=yes)	40m 55s
🍎 macOS / Template (target=template_release)	30m 30s
🐧 Linux / Editor w/ Mono (target=editor)	34m 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)	36m 36s
🍏 iOS / Template (target=template_release)	14m 18s
🌐 Web / Template (target=template_release)	20m 54s
🤖 Android / Template (target=template_release)	27m 35s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	30m 6s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	26m 40s
🐧 Linux / Template w/ Mono (target=template_release)	22m 14s
🏁 Windows / Editor (target=editor, tests=yes)	41m 46s
🐧 Linux / Minimal template (target=template_release, everything disabled)	14m 28s
🏁 Windows / Template (target=template_release)	30m 38s
🪲 Godot CPP / Build and test Godot CPP	6m 56s
	6h 21m 4s

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