fix: redact the password to ****** in API examples

[lafirest]

fix #10222

Fixes

Summary

🤖 Generated by Copilot at 11b3264

Mask password values in example request bodies for various bridge and authentication APIs. This improves the security and documentation quality of the code. The changes affect files in apps/emqx_authn, apps/emqx_bridge, and lib-ee/emqx_ee_bridge.

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
• 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
• If there should be document changes, a PR to emqx-docs.git is sent, or a jira ticket is created to follow up
• 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 4605671728

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 30 unchanged lines in 9 files lost coverage.
• Overall coverage increased (+0.02%) to 81.072%

---

Files with Coverage Reduction	New Missed Lines	%
apps/emqx_bridge/src/emqx_bridge.erl	1	91.2%
apps/emqx_dashboard/src/emqx_dashboard_monitor.erl	1	65.28%
apps/emqx_gateway/src/mqttsn/emqx_sn_channel.erl	1	73.13%
apps/emqx_machine/src/emqx_machine.erl	1	77.42%
apps/emqx_resource/src/emqx_resource_buffer_worker_sup.erl	2	86.96%
apps/emqx/src/emqx_logger_textfmt.erl	2	56.82%
apps/emqx/src/emqx_metrics_worker.erl	2	91.01%
apps/emqx_resource/src/emqx_resource_manager.erl	5	88.94%
apps/emqx/src/emqx_reason_codes.erl	15	86.76%

Totals
Change from base Build 4603373034:	0.02%
Covered Lines:	25061
Relevant Lines:	30912

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💛 - Coveralls