devs: fix typo in testdata for gochecknoglobals (#4320)

test/testdata/gochecknoglobals.go

@@ -11,7 +11,7 @@ var noGlobalsVar int // want "noGlobalsVar is a global variable"
 var ErrSomeType = errors.New("test that global errors aren't warned")
 
 var (
-	OnlyDigites = regexp.MustCompile(`^\d+$`)
+	OnlyDigits  = regexp.MustCompile(`^\d+$`)
 	BadNamedErr = errors.New("this is bad") // want "BadNamedErr is a global variable"
 )