feat(banned): add a new API used to clear all banned data

[lafirest]

A follow-up PR of this #11424.

Summary

🤖 Generated by Copilot at 2fc0468

Added a new API endpoint and a database function for clearing all banned data in emqx. The clear endpoint in emqx_mgmt_api_banned calls the clear/0 function in emqx_banned to delete all records of banned clients and topics. The endpoint also has a description and a label in different languages in rel/i18n/emqx_mgmt_api_banned.hocon.

PR Checklist

Please convert it to a draft if any of the following conditions are not met. Reviewers may skip over until all the items are checked:

• Added tests for the changes
• Added property-based tests for code which performs user input validation
• Changed lines covered in coverage report
• Change log has been added to changes/(ce|ee)/(feat|perf|fix)-<PR-id>.en.md files
• For internal contributor: there is a jira ticket to track this change
• Created PR to emqx-docs if documentation update is required, or link to a follow-up jira ticket
• Schema changes are backward compatible

Checklist for CI (.github/workflows) changes

• If changed package build workflow, pass this action (manual trigger)
• Change log has been added to changes/ dir for user-facing artifacts update

[coveralls]

Pull Request Test Coverage Report for Build 5831127970

• 4 of 4 (100.0%) changed or added relevant lines in 2 files are covered.
• 34 unchanged lines in 12 files lost coverage.
• Overall coverage decreased (-0.006%) to 81.339%

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Files with Coverage Reduction	New Missed Lines	%
apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_consumer_worker.erl	1	93.72%
apps/emqx_bridge_http/src/emqx_bridge_http_connector.erl	1	71.67%
apps/emqx_connector/src/emqx_connector_jwt_worker.erl	1	89.47%
apps/emqx_durable_storage/src/emqx_ds_message_storage_bitmask.erl	1	94.63%
apps/emqx_gateway_exproto/src/emqx_exproto_gcli.erl	1	64.15%
apps/emqx_gateway_mqttsn/src/emqx_mqttsn_channel.erl	1	73.78%
apps/emqx/src/emqx_banned.erl	1	89.86%
apps/emqx/src/emqx_logger_jsonfmt.erl	1	84.92%
apps/emqx/src/emqx_ws_connection.erl	1	76.37%
apps/emqx_ft/src/emqx_ft_storage_fs.erl	2	82.84%

Totals
Change from base Build 5830810370:	-0.006%
Covered Lines:	32220
Relevant Lines:	39612

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💛 - Coveralls