Обсуждение: pgsql: ci: Simplify ci-os-only handling

ci: Simplify ci-os-only handling

Handle 'ci-os-only' occurrences in the .cirrus.star file instead of
.cirrus.tasks.yml file. Now, 'ci-os-only' occurrences are controlled
from one central place instead of dealing with them in each task.

Author: Andres Freund <andres@anarazel.de>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/20240413021221.hg53rvqlvldqh57i%40awork3.anarazel.de
Backpatch: 15-, where CI support was added

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/4900179e9cd8965372fa9971b36c2898d53ebedc

Modified Files
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.cirrus.star      | 38 +++++++++++++++++++++++++++++++++++++-
.cirrus.tasks.yml | 17 ++++++++---------
2 files changed, 45 insertions(+), 10 deletions(-)