Trim stub header comments and redundant explanations

- Drop the 'Stub file ... BUILD_RTI=OFF / Auto-generated' headers from the
  tab_* and pdm_* stub files (RTI is gone on this branch; the names say it)
- Drop stub comments from MockCoordTrans.h and the coordTransTests placeholders
- Drop the DDS exclusion list comment from Lts/Common/CMakeLists.txt
- Shorten the staging and packages-out comments in new_docker_build.sh

qt6-after/qt6-migrated-legatus/Lts/Common/CommonUnitTestsPlaceholder/coordTransTests_smoke.cpp

@@ -1,4 +1,4 @@
-// Stub QtTest smoke test for coordTrans
+
 #include <QTest>
 
 class CoordTransSmokeTest : public QObject