Feature: request specific 'web3_clientVersion' response on switch over

@sambacha is already working on this.

Since May 9, 2022.

## request specific 'web3_clientVersion' response on switch over

when requesting switch, DApps may want to specify a specific `backing node` (i.e. the specific client node to connect to).

1. provide definition of a `backing node`
2. add optional parameter that can be defined requesting a specific `web3_clientVersion` response to successfully connect

example source: https://github.com/0xProject/tools/blob/7e7e6dc16c7ba5a8c13c3c5fbd418f3d77f251f0/web3-wrapper/src/web3_wrapper.ts#L249

```typescript
/**
* Retrieves the transaction receipt for a given transaction hash if found
* @param txHash Transaction hash
* @returns The transaction receipt, including it's status (0: failed, 1: succeeded). Returns undefined if transaction not found.
*/
public async getTransactionReceiptIfExistsAsync(txHash: string): Promise {
assert.isHexString('txHash', txHash);
const transactionReceiptRpc = await this.sendRawPayloadAsync({
method: 'eth_getTransactionReceipt',
params: [txHash],
});
// HACK Parity can return a pending transaction receipt. We check for a non null
// block number before continuing with returning a fully realised receipt.
// ref: https://github.com/paritytech/parity-ethereum/issues/1180
if (transactionReceiptRpc !== null && transactionReceiptRpc.blockNumber !== null) {
transactionReceiptRpc.status = Web3Wrapper._normalizeTxReceiptStatus(transactionReceiptRpc.status);
const transactionReceipt = marshaller.unmarshalTransactionReceipt(transactionReceiptRpc);
return transactionReceipt;
} else {
return undefined;
}
}
```