Removes Snowbridge parachain directory (#3186)

Removes the `bridges/snowbridge/parachain` directory and moves
everything up to under `snowbridge` directly. We are cleaning up our
local dev env after merging our crates into the polkadot-sdk.

---------

Co-authored-by: claravanstaden <Cats 4 life!>

bridges/snowbridge/scripts/hexliteral.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+# Creates a string constant from STDIN
+echo "const DATA: &'static str = concat!("
+cat - | fold | sed 's/^.*/\t"&",/'
+echo ");"