Add configuration for PollingHttpClient polling interval

[ciprianjichici]

Add configuration for PollingHttpClient polling interval

The issue or feature being addressed

The PollingHttpClient uses a fixed 10 second polling interval which prevents the completion of very short requests.

Details on the issue fix or feature implementation

Add a configuration entry to control the size of the polling interval.

Confirm the following

• I started this PR by branching from the head of the default branch
• I have targeted the PR to merge into the default branch
• This PR needs to be cherry-picked into at least one release branch
• I have included unit tests for the issue/feature
• I have included inline docs for my changes, where applicable
• I have successfully run a local build
• I have provided the required update scripts, where applicable
• I have updated relevant docs, where applicable

Note

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