Add config to get the totalResults by user count

[asha15]

Proposed changes in this pull request

Resolve the issue: wso2/product-is#12813

When the SCIM API is invoked with a filter, the current behavior involves returning a predefined value for the totalResults parameter based on the MaxUserNameListLength, rather than reflecting the actual results that match the filter criteria. This fix addresses the issue by accurately determining the user count that corresponds to the given filter. To enable this fix, the following config should be added

[scim2]
enable_group_based_user_filter_improvements = true

Related PRs: wso2-extensions/identity-inbound-provisioning-scim2#533, wso2/carbon-kernel#3906

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[mpmadhavig]

What's the reason for commenting this out?

[jenkins-is-staging]

PR builder started
Link: https://github.com/wso2/product-is/actions/runs/8628566269

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PR builder completed
Link: https://github.com/wso2/product-is/actions/runs/8628566269
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Approving the pull request based on the successful pr build https://github.com/wso2/product-is/actions/runs/8628566269