tdf#124176 Use pragma once instead of include guards

Changes include guards in threadmanager.hxx to #pragma once

Change-Id: I9cdc391f68389b0e23fa52598f5c2f1281d4e7a5
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/91080
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>
diff --git a/sw/source/core/docnode/threadmanager.hxx b/sw/source/core/docnode/threadmanager.hxx
index 21078e7..cdadd42 100644
--- a/sw/source/core/docnode/threadmanager.hxx
+++ b/sw/source/core/docnode/threadmanager.hxx
@@ -16,8 +16,8 @@
 *   except in compliance with the License. You may obtain a copy of
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */
#ifndef INCLUDED_SW_SOURCE_CORE_DOCNODE_THREADMANAGER_HXX
#define INCLUDED_SW_SOURCE_CORE_DOCNODE_THREADMANAGER_HXX

#pragma once

#include <vcl/idle.hxx>
#include <osl/mutex.hxx>
@@ -143,6 +143,5 @@

        bool StartThread( const tThreadData& aThreadData );
};
#endif

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