cmd,internal: fix comment typos

cmd/era/main.go

@@ -269,7 +269,7 @@ func checkAccumulator(e *era.Era) error {
 	//      the blocks are all correct (via hash)
 	//
 	// The attributes 1), 2), and 3) are checked for each block. 4) and 5) require
-	// accumulation accross the entire set and are verified at the end.
+	// accumulation across the entire set and are verified at the end.
 	for it.Next() {
 		// 1) next() walks the block index, so we're able to implicitly verify it.
 		if it.Error() != nil {

internal/era/e2store/e2store_test.go

@@ -90,7 +90,7 @@ func TestDecode(t *testing.T) {
 		{ // basic valid decoding
 			have: "ffff000000000000",
 		},
-		{ // basic valid decoding
+		{ // basic invalid decoding
 			have: "ffff000000000001",
 			err:  fmt.Errorf("reserved bytes are non-zero"),
 		},