Mark all *.sh files in usr/share/opentelemetry_shell/ as executable

All *.sh files under usr/share/opentelemetry_shell/ should have the executable bit set (e.g. chmod +x).

Assumption: filing this as a general cleanup/fix task without deeper investigation into which specific files currently lack the executable bit or how it happened (e.g. git checkout, packaging step, etc.) — let me know if you'd like that investigated first.