LocalHttpPort not honored in VS

See the sample of [local.settings.json](https://docs.microsoft.com/en-us/azure/azure-functions/functions-run-local#local-settings-file). It says

>The --port command-line option takes precedence over this value.

Is it the reason that LocalHttpPort doesn't work in VS(set --port 7071 somewhere by default) , while using the standalone CLI installed by npm it does? Both CLI have the same version.

```
Azure Functions Core Tools (2.1.748 Commit hash: 5db20665cf0c11bedaffc96d81c9baef7456acb3)
Function Runtime Version: 2.0.12134.0

Start by comparing how Visual Studio invokes Azure Functions Core Tools with the standalone CLI, focusing on whether VS supplies a default --port value. Check the local.settings.json LocalHttpPort behavior and command-line precedence described in the linked documentation. Done means determining why VS ignores LocalHttpPort and defining the required behavior when no explicit port is configured.

Written by the indexing model from the issue text.