Fix banner placement exception breaking flags

[Pablete1234]

Fixes #992

The issue was that when a banner was placed, it caused block updates which could cause that newly placed banner to pop-out, causing a cast exception when trying to use the block metadata as a banner.

This pr addresses the issue in 2 ways:

• Do not apply physics when placing banners, this removes the block updates that pop-out the banner
• Check if the block state is a banner before doing anything with it. This prevents the exception that could cause the banner to become unpickable (since label entity doesn't get to initialize).