bash error handling and reporting is atrocious. Without -e it will
just ignore errors. With -e it will stop on errors, but not report
where the error happened (apart from exiting itself with an error code).
Improve that with the `trap ERR` command. Note that this won't be invoked
on intentional error exit with `exit 1`.
We apply this on every bash script that contains -e or that it appears
trivial to set it in. Non-trivial scripts without -e are left unmodified,
since they might intentionally invoke failing scripts.
Closesscylladb/scylladb#22747
Since 3c7af28725, the cqlsh submodule no longer contains a
bin/cqlsh shell script. This broke the supermodule's bin/cqlsh
shortcut.
Fix it by invoking cqlsh.py directly.
Closesscylladb/scylladb#20591
