Fixes two locales

config/locales/en.yml

@@ -48,7 +48,7 @@ en:
         work_package:
           attributes:
             blocks_ids:
-              can_only_contain_work_packages_of_current_sprint: "can only contain the IDs of current sprint's tickets"
+              can_only_contain_work_packages_of_current_sprint: "can only contain the IDs of work packages in the current sprint"
               must_block_at_least_one_work_package: "must contain the ID of at least one ticket"
             fixed_version_id:
               task_version_must_be_the_same_as_story_version: "must be the same as the story's version"
@@ -77,7 +77,7 @@ en:
     label_is_done_status: "Status %{status_name} means done"
     no_burndown_data: "No burndown data available. It is necessary to have the sprint start- and end dates set."
     points: "Points"
-    positions_could_not_be_rebuilt: "Positions could not be rebuild."
+    positions_could_not_be_rebuilt: "Positions could not be rebuilt."
     positions_rebuilt_successfully: "Positions rebuilt successfully."
     properties: "Properties"
     rebuild: "Rebuild"