test: move common.PORT tests to sequential

Reasons:

- `test-async-wrap-getasyncid` binds a handle, so move to
  sequential because port cannot be already in use.
- `test-dgram-implicit-bind-failure` requires a hardcoded
  port number to properly send socket packet.
- `test-http-agent-uninitialized-with-handle` requires a
  hardcoded port number to properly send http request.
- `test-http-agent-uninitialized` requires a hardcoded port
  number to properly send http request.
- `test-net-localport` requires a hardcoded port number
  for assertions.

In addition this replaces two common.PORTs with a dynamic port.

PR-URL: #15151
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

test/parallel/test-http-agent-uninitialized-with-handle.js

@@ -13,11 +13,12 @@ socket._handle = {
   ref() { },
   readStart() { },
 };
-const req = new http.ClientRequest(`http://localhost:${common.PORT}/`);
 
 const server = http.createServer(common.mustCall((req, res) => {
   res.end();
-})).listen(common.PORT, common.mustCall(() => {
+})).listen(0, common.mustCall(() => {
+  const req = new http.ClientRequest(`http://localhost:${server.address().port}/`);
+
   // Manually add the socket without a _handle.
   agent.freeSockets[agent.getName(req)] = [socket];
   // Now force the agent to use the socket and check that _handle exists before

test/parallel/test-http-agent-uninitialized.js

@@ -8,11 +8,12 @@ const agent = new http.Agent({
   keepAlive: true,
 });
 const socket = new net.Socket();
-const req = new http.ClientRequest(`http://localhost:${common.PORT}/`);
 
 const server = http.createServer(common.mustCall((req, res) => {
   res.end();
-})).listen(common.PORT, common.mustCall(() => {
+})).listen(0, common.mustCall(() => {
+  const req = new http.ClientRequest(`http://localhost:${server.address().port}/`);
+
   // Manually add the socket without a _handle.
   agent.freeSockets[agent.getName(req)] = [socket];
   // Now force the agent to use the socket and check that _handle exists before