Support configuring http client related configs with regard to action execution at server level

[malithie]

Is your suggestion related to an experience ? Please describe.
When it comes to implementing extensions as network extensions, the extension execution framework is basically invoking external HTTP endpoints.
Here, there are some associated configurations that we should allow to configure at server level to fine tune the deployment based on requirements. This includes, http read time out, connection time out, connection poll size, etc.
Also, in a read time out or connection time out the execution retries by default. It should be possible to configure this retry count as well.

Describe the improvement
Have facility to configure following related to the http calls initiated from IS to the external service implementing the extension.

• HTTPReadTimeout

• HTTPConnectionRequestTimeout

• HTTPConnectionTimeout

• HTTPConnectionPoolSize

• RetryCount in case of a connection error

• Implement reading configurations at the server level

• Cover the documentation for Identity Server