fix(sdk-api): fix proxy-agent usage

We removed the superagent-proxy earlier to use proxy-agent.
The change missed some old usage.

Change the proxy-agent version to 5.0. This is the version
that was used under the hood. The new version requires setting
proxy url in the environment variable. It does not quite fit how
we use the proxy-agent currently.

Ticket: WP-1185

Author: pengyuc-bitgo

modules/sdk-api/package.json

@@ -62,7 +62,7 @@
     "debug": "3.1.0",
     "eol": "^0.5.0",
     "lodash": "^4.17.15",
-    "proxy-agent": "6.3.1",
+    "proxy-agent": "5.0.0",
     "sanitize-html": "^2.11",
     "secp256k1": "^4.0.2",
     "secrets.js-grempe": "^1.1.0",

modules/sdk-api/src/bitgoAPI.ts

@@ -98,7 +98,7 @@ const TransactionBuilder = require('./v1/transactionBuilder');
 let proxyAgent: any;
 if (!isBrowser && !isWebWorker) {
   debug('enabling proxy-agent');
-  proxyAgent = require('proxy-agent').ProxyAgent;
+  proxyAgent = require('proxy-agent');
 }
 
 const patchedRequestMethods = ['get', 'post', 'put', 'del', 'patch'] as const;
@@ -574,7 +574,13 @@ export class BitGoAPI implements BitGoBase {
     // Proxy settings must still be respected however
     const resultPromise = this.getAgentRequest('get', this.url('/client/constants'));
     resultPromise.set('BitGo-SDK-Version', this._version);
-    const result = await (this._proxy ? resultPromise.proxy(this._proxy) : resultPromise);
+    if (this._proxy) {
+      const agent = new proxyAgent(this._proxy);
+      if (agent) {
+        resultPromise.agent(agent);
+      }
+    }
+    const result = await resultPromise;
     BitGoAPI._constants[env] = result.body.constants;
 
     if (result.body?.ttl && typeof result.body?.ttl === 'number') {