refactor: tighten up cloudflare detection

The previous approach to detecting whether to use Cloudflare's sockets was to check for missing polyfills.
But as we improve the polyfills that Wrangler can provide these checks are no longer valid.

Now we just try to use the Cloudflare API first and fallback to Node.js if those are not available.

packages/pg/lib/stream.js

@@ -3,12 +3,12 @@
  * @returns {Duplex}
  */
 module.exports.getStream = function getStream(ssl) {
-  const net = require('net')
-  if (typeof net.Socket === 'function') {
-    return new net.Socket()
-  } else {
+  try {
     const { CloudflareSocket } = require('pg-cloudflare')
     return new CloudflareSocket(ssl)
+  } catch {
+    const net = require('net')
+    return new net.Socket()
   }
 }
 
@@ -18,11 +18,11 @@ module.exports.getStream = function getStream(ssl) {
  * @returns {Duplex}
  */
 module.exports.getSecureStream = function getSecureStream(options) {
-  var tls = require('tls')
-  if (tls.connect) {
-    return tls.connect(options)
-  } else {
+  try {
     options.socket.startTls(options)
     return options.socket
+  } catch {
+    var tls = require('tls')
+    return tls.connect(options)
   }
 }