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_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/4da1f66fae836c4579ea38fe6d1d8fa2e6e9faf2

Modified Files
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.cirrus.tasks.yml | 12 ++++++++++++
1 file changed, 12 insertions(+)