Fix TileSet editor create/remove tiles selection rect drawing #131

Job	Run time
📊 Static checks / Code style, file formatting, and docs	4m 10s
🍎 macOS / Editor (target=editor, tests=yes)	22m 2s
🍏 iOS / Template (target=template_release)	20m 47s
🤖 Android / Template (target=template_release)	30m 34s
🍎 macOS / Template (target=template_release)	14m 35s
🐧 Linux / Editor w/ Mono (target=editor)	39m 23s
🐧 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)	37m 49s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	35m 49s
🌐 Web / Template w/ threads (target=template_release, threads=yes)	22m 48s
🏁 Windows / Editor (target=editor, tests=yes)	45m 23s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	30m 34s
🌐 Web / Template w/o threads (target=template_release, threads=no)	22m 33s
🏁 Windows / Template (target=template_release)	35m 43s
🐧 Linux / Template w/ Mono (target=template_release)	24m 45s
🐧 Linux / Minimal template (target=template_release, everything disabled)	13m 44s
🪲 Godot CPP / Build and test Godot CPP	7m 2s
	6h 47m 41s

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