Fixed xContent changes

[Angie-Zhang]

Description

Fixed build failure due to OSCore xContent changes

Issues Resolved

#645

Check List

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[codecov-commenter]

Codecov Report

Merging #646 (836394d) into 2.x (974dba3) will increase coverage by 0.01%.
The diff coverage is n/a.

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@@             Coverage Diff              @@
##                2.x     #646      +/-   ##
============================================
+ Coverage     61.36%   61.38%   +0.01%     
  Complexity      112      112              
============================================
  Files            73       73              
  Lines          2472     2473       +1     
  Branches        265      265              
============================================
+ Hits           1517     1518       +1     
  Misses          778      778              
  Partials        177      177              

Flag	Coverage Δ
opensearch-notifications	61.38% <ø> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...earch/notifications/core/NotificationCorePlugin.kt	84.61% <ø> (ø)
...org/opensearch/notifications/core/utils/Helpers.kt	100.00% <ø> (ø)
...org/opensearch/notifications/NotificationPlugin.kt	97.43% <ø> (ø)
...fications/action/CreateNotificationConfigAction.kt	81.81% <ø> (ø)
...fications/action/DeleteNotificationConfigAction.kt	81.81% <ø> (ø)
...earch/notifications/action/GetChannelListAction.kt	81.81% <ø> (ø)
...otifications/action/GetNotificationConfigAction.kt	81.81% <ø> (ø)
...ch/notifications/action/GetPluginFeaturesAction.kt	84.61% <ø> (ø)
.../notifications/action/PublishNotificationAction.kt	72.72% <ø> (ø)
...rch/notifications/action/SendNotificationAction.kt	81.81% <ø> (ø)
... and 9 more

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[Angie-Zhang]

Failed workflows will be fixed/removed in #647