pgsql: ci: Add missing "set -e" to scripts run by su.

ci: Add missing "set -e" to scripts run by su.

If any shell command fails, the whole script should fail. To avoid
future omissions, add this even for single-command scripts that use su
with heredoc syntax, as they might be extended or copied-and-pasted.

Extracted from a larger patch that wanted to use #error during
compilation, leading to the diagnosis of this problem.

Reviewed-by: Tristan Partin <tristan(at)partin(dot)io> (earlier version)
Discussion: https://postgr.es/m/DDZP25P4VZ48.3LWMZBGA1K9RH%40partin.io
Backpatch-through: 15

Branch
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REL_18_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ae2381025a4c77662ed5a56c062cbf3355c3d618

Modified Files
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.cirrus.tasks.yml | 16 ++++++++++++++++
1 file changed, 16 insertions(+)