ra/SAPHanaRA* - HANA_CALL - use defined execution shell

[PeterPitterling]

currently SIDadms login shell could be sh,bash and csh. Because of different default settings (e.g., expand_aliases) and shell behaviors, coding and testing is unnecessary complicated. The su command allows the specification of the executing shell. By providing a fixed shell (sh, bash) this would always provide a defined runtime environment.

su - SIDadm -s /bin/sh -c '(cd $DIR_INSTANCE/exe/python_support; python landscapeHostConfiguration.py)'
su - SIDadm -s /bin/bash -c '(cd $DIR_INSTANCE/exe/python_support; python landscapeHostConfiguration.py)'

https://man7.org/linux/man-pages/man1/su.1.html

-s, --shell=shell
Run the specified shell instead of the default. The shell to
run is selected according to the following rules, in order: