Skull charge, flow and guster banner patterns are not mirrored on the backside

Bedrock Edition repost of MC-269359 (fixed in 1.21 Pre-Release 2).

Skull charge, flow and guster banner patterns are not mirrored on the backside, which is inconsistent with other asymmetric patterns.

Steps to Reproduce:

1. Apply the banner patterns mentioned above onto a banner.
2. Place the banner down.
3. Walk to the back of the banner.

Observed Results:
Skull charge, flow and guster banner patterns are not mirrored on the backside.

Expected Results:
Skull charge, flow and guster banner patterns should be mirrored on the backside.