The `generate` RPC method:
- was introduced in 2010
- is now only used for testing
- reaches across multiple components (wallet, mining)

I propose we remove the wallet `generate` RPC method and update all tests to use the `generatetoaddress` RPC method. We can do this non-invasively in the test framework by adding a `generate` method to `TestNode` so that the individual tests do not need to be updated. We could also add a `generate` alias to the `generatetoaddress` RPC method.

Doing this removes a wallet->server dependency and simplifies the wallet->server interface (#10973).

I'm opening this issue before implementing in case anyone has objections.
#include <amount.h>
#include <chain.h>
#include <chainparams.h>
#include <consensus/consensus.h>
#include <consensus/params.h>
#include <consensus/validation.h>
#include <core_io.h>
#include <key_io.h>
#include <miner.h>
#include <net.h>
#include <policy/fees.h>
#include <pow.h>
#include <rpc/blockchain.h>
#include <rpc/mining.h>
#include <rpc/server.h>
#include <shutdown.h>
#include <txmempool.h>
#include <util.h>
#include <utilstrencodings.h>
#include <validation.h>
#include <validationinterface.h>
#include <versionbitsinfo.h>
#include <warnings.h>
#include <memory>
#include <stdint.h>
unsigned int ParseConfirmTarget(const UniValue& value)