Log the "durableTask" section of host.json on host startup

#### What problem would the feature you're requesting solve? Please describe.
I'm trying to investigate issues related to Durable Functions and I'm not able to see the host.json configuration values that the customer supplied.

#### Describe the solution you'd like
I would like to see the [durableTask](https://docs.microsoft.com/en-us/azure/azure-functions/durable/durable-functions-bindings#host-json) section of host.json included in the host.json logging. This will make diagnosing issues related misconfiguration easier.

#### Describe alternatives you've considered
Alternatively the Durable extension could dump the host.json information it sees. However, there are a few issues with this:
* It can only dump information that it sees. If a customer applies config to a misnamed section, then we probably won't see it and can't log it.
* This won't help customers who are using previous versions of our extension since we don't force them to upgrade.
* It would be ideal if the host.json configuration log consistently provided all host.json settings instead of relying on extension authors to do this.

#### Additional context
N/A

No source files, tests, or entry points are named in the issue. Start by locating the host.json startup-logging implementation and the Durable Functions configuration handling, then verify that the durableTask section supplied by customers appears in host startup logs without relying on the extension to emit it.

Written by the indexing model from the issue text.