Fix typo in compiler/sem/guards.nim #174

Job	Run time
Provide additional context for the workflow	5s
Build release binaries (Linux)	7m 3s
Build release binaries (macOS)	6m 35s
Build release binaries (macOS (M1))	4m 5s
Build release binaries (Windows)	11m 9s
Build source archive	2m 56s
Build docs and release artifacts (Linux)	7m 30s
Build and test tooling (Linux)	2m 50s
Build docs and release artifacts (macOS)	12m 8s
Test the compiler and stdlib (Linux, batch #0)	5m 59s
Build and test tooling (macOS)	4m 55s
Build and test tooling (macOS (M1))	2m 1s
Test the compiler and stdlib (Linux, batch #1)	5m 27s
Build and test tooling (Windows)	3m 35s
Test the compiler and stdlib (macOS, batch #0)	6m 33s
Build docs and release artifacts (macOS (M1))	4m 16s
Test the compiler and stdlib (macOS, batch #1)	6m 15s
Build docs and release artifacts (Windows)	10m 26s
Test the compiler and stdlib (macOS (M1), batch #0)	5m 23s
Test the compiler and stdlib (macOS (M1), batch #1)	4m 24s
Test the compiler and stdlib (Windows, batch #0)	10m 21s
Test the compiler and stdlib (Windows, batch #1)	11m 14s
Build release artifacts from source archive (Linux)	10m 37s
Build release artifacts from source archive (macOS)	8m 45s
Build release artifacts from source archive (macOS (M1))	4m 56s
Build release artifacts from source archive (Windows)	19m 10s
Test release artifacts	43s
All check passed	1s
	2h 59m 22s

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