Remove 1inch token list (#81)

The 1inch token list is used to decrease the number of network requests
when fetching token information from the node.
The related API has been broken since a long time, so there is no actual
efficiency gain from using this list.
The [updated version of their token
API](https://portal.1inch.dev/documentation/tokens/quick-start) requires
an API key, which is by far not worth it for this use case.

Pruning this code also removes the very annoying warning "unable to
recover token list from 1inch" that is shown on every invocation of a
Hardhat command, since the list is prefetched to make execution faster.

### Test Plan

Code compiles.

src/tasks/selfSell.ts

@@ -37,7 +37,6 @@ import {
   SupportedNetwork,
 } from "./ts/deployment";
 import { createGasEstimator, IGasEstimator } from "./ts/gas";
-import { fastTokenDetails } from "./ts/oneinch_tokens";
 import {
   DisappearingLogFunctions,
   promiseAllWithRateLimit,
@@ -296,7 +295,7 @@ async function getOrders({
   const computeOrderInstructions = tokens.map(
     (tokenAddress) =>
       async ({ consoleLog }: DisappearingLogFunctions) => {
-        const sellToken = await fastTokenDetails(tokenAddress, hre);
+        const sellToken = await erc20Token(tokenAddress, hre);
         if (sellToken === null) {
           throw new Error(
             `There is no valid ERC20 token at address ${tokenAddress}`,

src/tasks/withdraw.ts

@@ -20,14 +20,13 @@ import {
   SupportedNetwork,
 } from "./ts/deployment";
 import { createGasEstimator, IGasEstimator } from "./ts/gas";
-import { fastTokenDetails } from "./ts/oneinch_tokens";
 import {
   DisappearingLogFunctions,
   promiseAllWithRateLimit,
 } from "./ts/rate_limits";
 import { getSolvers } from "./ts/solver";
 import { Align, displayTable } from "./ts/table";
-import { Erc20Token } from "./ts/tokens";
+import { erc20Token, Erc20Token } from "./ts/tokens";
 import {
   formatTokenValue,
   formatUsdValue,
@@ -246,7 +245,7 @@ async function getWithdrawals({
   const computeWithdrawalInstructions = tokens.map(
     (tokenAddress) =>
       async ({ consoleLog }: DisappearingLogFunctions) => {
-        const token = await fastTokenDetails(tokenAddress, hre);
+        const token = await erc20Token(tokenAddress, hre);
         if (token === null) {
           throw new Error(
             `There is no valid ERC20 token at address ${tokenAddress}`,