Replace use of typed-rest-client with @actions/http-client (#634)

Fixes #630

sources/src/wrapper-validation/checksums.ts

@@ -1,6 +1,6 @@
-import * as httpm from 'typed-rest-client/HttpClient'
 import * as cheerio from 'cheerio'
 import * as core from '@actions/core'
+import * as httpm from '@actions/http-client'
 
 import fileWrapperChecksums from './wrapper-checksums.json'
 
@@ -69,8 +69,20 @@ async function httpGetJsonArray(url: string): Promise<unknown[]> {
 }
 
 async function httpGetText(url: string): Promise<string> {
-    const response = await httpc.get(url)
-    return await response.readBody()
+    const maxAttempts = 4
+    let attempts = 0
+    while (attempts < maxAttempts) {
+        try {
+            const response = await httpc.get(url)
+            return await response.readBody()
+        } catch (error) {
+            attempts++
+            if (attempts === maxAttempts) {
+                return new Promise((_resolve, reject) => reject(error))
+            }
+        }
+    }
+    return new Promise((_resolve, reject) => reject(new Error('Illegal state')))
 }
 
 async function addDistributionSnapshotChecksumUrls(checksumUrls: [string, string][]): Promise<void> {