dumpspirv: README typo fix #816

Job	Run time
Rocky Linux MinGW	55s
FreeBSD	1m 5s
Rocky Linux	1m 41s
iOS/tvOS SDL3 (iOS, iphoneos, arm64)	50s
iOS/tvOS SDL3 (iOS, iphonesimulator, x86_64;arm64)	1m 0s
Rocky Linux MinGW SDL3	52s
Debian Linux PPC	1m 41s
iOS/tvOS SDL3 (tvOS, appletvos, arm64)	53s
Debian Linux PPC SDL3	57s
iOS/tvOS SDL3 (tvOS, appletvsimulator, x86_64;arm64)	53s
Rocky Linux SDL3	1m 35s
macOS (x86_64)	48s
macOS (Universal) SDL3	1m 5s
Windows (MSVC)	1m 40s
	15m 55s

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