Set reserved nodes with offchain worker. (#6996)

* add offchain worker api to set reserved nodes.

* new offchain api to get node public key.

* node public key from converter

* refactor set reserved nodes ocw api.

* new ndoe authorization pallet

* remove unnecessary clone and more.

* more

* tests for node authorization pallet

* remove dependency

* fix build

* more tests.

* refactor

* Update primitives/core/src/offchain/testing.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update frame/node-authorization/src/lib.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update frame/node-authorization/src/lib.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update frame/node-authorization/src/lib.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* format code

* expose NetworkService

* remove NetworkStateInfo in offchain

* replace NodePublicKey with PeerId.

* set max length of peer id.

* clear more

* use BTreeSet for set of peers.

* decode opaque peer id.

* extract NetworkProvider for client offchain.

* use OpaquePeerId in node authorization pallet.

* fix test

* better documentation

* fix test

* doc

* more fix

* Update primitives/core/src/offchain/mod.rs

Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>

* Update client/offchain/src/api.rs

Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>

* derive serialize and deserialize

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>
Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>

substrate/frame/im-online/src/tests.rs

@@ -21,8 +21,8 @@
 
 use super::*;
 use crate::mock::*;
+use sp_core::OpaquePeerId;
 use sp_core::offchain::{
-	OpaquePeerId,
 	OffchainExt,
 	TransactionPoolExt,
 	testing::{TestOffchainExt, TestTransactionPoolExt},