RPC: Allow the sendTransaction preflight commitment level to be configured (bp #11792) (#11793)

* Allow the sendTransaction preflight commitment level to be configured

(cherry picked from commit b660704faa)

# Conflicts:
#	cli/src/cli.rs
#	core/src/rpc.rs

* rebase

Co-authored-by: Michael Vines <mvines@gmail.com>

tokens/src/thin_client.rs

@@ -35,6 +35,7 @@ impl Client for RpcClient {
             &transaction,
             RpcSendTransactionConfig {
                 skip_preflight: true,
+                ..RpcSendTransactionConfig::default()
             },
         )
         .map_err(|e| TransportError::Custom(e.to_string()))