http-client: convert to ESM

packages/http-client/src/auth.ts

@@ -1,6 +1,6 @@
 import * as http from 'http'
-import * as ifm from './interfaces'
-import {HttpClientResponse} from './index'
+import * as ifm from './interfaces.js'
+import {HttpClientResponse} from './index.js'
 
 export class BasicCredentialHandler implements ifm.RequestHandler {
   username: string

packages/http-client/src/index.ts

@@ -2,9 +2,9 @@
 
 import * as http from 'http'
 import * as https from 'https'
-import * as ifm from './interfaces'
+import * as ifm from './interfaces.js'
 import * as net from 'net'
-import * as pm from './proxy'
+import * as pm from './proxy.js'
 import * as tunnel from 'tunnel'
 import {ProxyAgent} from 'undici'
 

packages/http-client/src/interfaces.ts

@@ -1,6 +1,6 @@
 import * as http from 'http'
 import * as https from 'https'
-import {HttpClientResponse} from './index'
+import {HttpClientResponse} from './index.js'
 
 export interface HttpClient {
   options(