chore(deps): update prom/alertmanager docker tag to v0.34.0

[dreadnode-renovate-bot]

This PR contains the following updates:

Package	Update	Change
prom/alertmanager	minor	v0.33.1 → v0.34.0

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Release Notes

prometheus/alertmanager (prom/alertmanager)

v0.34.0: 0.34.0 / 2026-08-16

Compare Source

• [CHANGE] notify: The reason label on alertmanager_notifications_failed_total now distinguishes authError (HTTP 401/403) and rateLimited (HTTP 429) from the generic clientError. Dashboards/alerts matching reason="clientError" for these codes must be updated. #​5332
• [FEATURE] Add optional templatable labels to alert routes. #​5328
• [FEATURE] eventrecorder: Add inhibit rule names to inhibition_muted_alert events. #​5315
• [FEATURE] eventrecorder: Add stdout output type. #​5311
• [FEATURE] silences: Add active, expired, and pending boolean filter parameters to GET /api/v2/silences to allow filtering silences by state server-side. #​5406
• [FEATURE] sns: Add aws external_id support in sigv4 configuration. #​5157
• [FEATURE] template: Add toDate and mustToDate functions. #​5327
• [ENHANCEMENT] doc: Add AlertmanagerClusterFailedPeers alertmanager-mixin. #​5301
• [ENHANCEMENT] doc: Add description for Rocketchat parameters in global config. #​5181
• [ENHANCEMENT] doc: Add top level tracing configuration key. #​5314
• [ENHANCEMENT] doc: Fix Alertmanager port in amtool config routes example. #​5312
• [ENHANCEMENT] eventrecorder: Add optional webhook batching. #​5392
• [ENHANCEMENT] notify: The discord and webex integrations now report a failure reason on alertmanager_notifications_failed_total. #​5332
• [ENHANCEMENT] ui: Improve responsiveness of UI when loading thousands of alerts. #​5357
• [BUGFIX] eventrecorder: Fixed a minor performance regression when the event recorder is enabled. #​5307
• [BUGFIX] msteamsv2: Inherit global proxy_url into partial http_config. #​5379
• [BUGFIX] webhook: Keep custom payload string values verbatim instead of reinterpreting JSON leaves that look like YAML (e.g. values ending with a colon). #​5304

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