server: ditch unmaintained "spdy"

HTTP/2 support can be restored after migration to fastify.

Bug: #524

package.json

@@ -112,7 +112,6 @@
     "@types/react-router-dom": "^5.3.3",
     "@types/react-transition-group": "^4.4.4",
     "@types/react-window": "^1.8.5",
-    "@types/spdy": "^3.4.5",
     "@types/supertest": "^2.0.12",
     "@types/tar-fs": "^2.0.1",
     "@types/yargs": "^17.0.10",
@@ -194,7 +193,6 @@
     "sass-loader": "^12.6.0",
     "saxen": "^8.1.2",
     "source-map-loader": "^3.0.1",
-    "spdy": "^4.0.2",
     "style-loader": "^3.3.1",
     "supertest": "^6.2.3",
     "tar-fs": "^2.1.1",

server/bin/web-server.ts

@@ -2,7 +2,7 @@ import chalk from 'chalk';
 import debug from 'debug';
 import fs from 'fs';
 import http from 'http';
-import spdy from 'spdy';
+import https from 'https';
 
 import app from '../app';
 import config from '../../config';
@@ -37,15 +37,15 @@ const startWebServer = () => {
   app.set('host', host);
 
   // Create HTTP or HTTPS server.
-  let server: http.Server | spdy.Server;
+  let server: http.Server | https.Server;
 
   if (useSSL) {
     if (!config.sslKey || !config.sslCert) {
       console.error('Cannot start HTTPS server, `sslKey` or `sslCert` is missing in config.js.');
       process.exit(1);
     }
 
-    server = spdy.createServer(
+    server = https.createServer(
       {
         key: fs.readFileSync(config.sslKey),
         cert: fs.readFileSync(config.sslCert),