Fix transaction pruning in tx-pool (#6276)

The `tree_route` generated by the import notification is only from the
old best block to the new best parent. This means, it does not contain
the new best block in `enacted()`. We need to prune the transactions of
the new best block "manually" to fix this bug.

Besides that, this pr also changed the `id` parameter of the `NewBlock`
chain event to `hash`. The hash of a block is unique in contrast to the
block number. (Block id can either be number or hash)

substrate/Cargo.lock

@@ -6745,10 +6745,12 @@ dependencies = [
  "parity-scale-codec",
  "parity-util-mem",
  "parking_lot 0.10.2",
+ "sc-block-builder",
  "sc-client-api",
  "sc-transaction-graph",
  "sp-api",
  "sp-blockchain",
+ "sp-consensus",
  "sp-core",
  "sp-keyring",
  "sp-runtime",