Remove stale xpack.slo.featureFeedbackButtonLabel translation entries

The i18n key was defined only in the deleted feedback_button.tsx; removing
it from all 4 translation files fixes the i18n CI check.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: jasonrhodes

x-pack/platform/plugins/private/translations/translations/de-DE.json

@@ -47498,7 +47498,6 @@
     "xpack.slo.errorRateChart.errorRateLabel": "Fehlerrate",
     "xpack.slo.eventsChartPanel.euiIcon.noResultsLabel": "keine Ergebnisse",
     "xpack.slo.extraInstanceIds.badge": "+{count, plural, one {# instance} other {# Instanzen}}",
-    "xpack.slo.featureFeedbackButtonLabel": "Feedback geben",
     "xpack.slo.featureRegistry.linkSloTitle": "SLOs",
     "xpack.slo.fieldSelector.all": "Alle",
     "xpack.slo.formattedConfigLabel.valid": "Es können nur gültige Formularkonfigurationen inspiziert werden.",

x-pack/platform/plugins/private/translations/translations/fr-FR.json

@@ -47337,7 +47337,6 @@
     "xpack.slo.errorRateChart.errorRateLabel": "Taux d'erreur",
     "xpack.slo.eventsChartPanel.euiIcon.noResultsLabel": "aucun résultat",
     "xpack.slo.extraInstanceIds.badge": "+{count, plural, one {# instance} other {# instances}}",
-    "xpack.slo.featureFeedbackButtonLabel": "Fournir des commentaires",
     "xpack.slo.featureRegistry.linkSloTitle": "SLO",
     "xpack.slo.fieldSelector.all": "Tous",
     "xpack.slo.formattedConfigLabel.valid": "Seules les configurations de formulaires valides peuvent être inspectées.",

x-pack/platform/plugins/private/translations/translations/ja-JP.json

@@ -47679,7 +47679,6 @@
     "xpack.slo.errorRateChart.errorRateLabel": "エラー率",
     "xpack.slo.eventsChartPanel.euiIcon.noResultsLabel": "結果なし",
     "xpack.slo.extraInstanceIds.badge": "+{count, plural, one {# instance} other {#件のインスタンス}}",
-    "xpack.slo.featureFeedbackButtonLabel": "フィードバックを送信",
     "xpack.slo.featureRegistry.linkSloTitle": "SLO",
     "xpack.slo.fieldSelector.all": "すべて",
     "xpack.slo.formattedConfigLabel.valid": "有効な形式の構成のみを検査できます。",

x-pack/platform/plugins/private/translations/translations/zh-CN.json

@@ -47669,7 +47669,6 @@
     "xpack.slo.errorRateChart.errorRateLabel": "错误率",
     "xpack.slo.eventsChartPanel.euiIcon.noResultsLabel": "无结果",
     "xpack.slo.extraInstanceIds.badge": "+{count, plural, one {# instance} other {# 个实例}}",
-    "xpack.slo.featureFeedbackButtonLabel": "反馈",
     "xpack.slo.featureRegistry.linkSloTitle": "SLO",
     "xpack.slo.fieldSelector.all": "全部",
     "xpack.slo.formattedConfigLabel.valid": "只能检查有效表单配置。",