build: remove random.Seed since random generator is seeded automatically in go1.20

Now that the minimum version is go1.20 we can stop seeding the random
number generator.

vfs/test_vfs/test_vfs.go

@@ -29,12 +29,6 @@ var (
 	testNumber atomic.Int32
 )
 
-// Seed the random number generator
-func init() {
-	_ = random.Seed()
-
-}
-
 // Test contains stats about the running test which work for files or
 // directories
 type Test struct {