pgsql: ci: Remove installation of libcurl

ci: Remove installation of libcurl

The CI images come with libcurl pre-installed since commit a119426
in the pg-vm-images repository so remove the installation commands
from the Cirrus tasks. Installation of libcurl packages was added
in the OAuth patchset which introduced the dependency, a backpatch
is thus not applicable.

Author: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: /messages/by-id/8745B9D8-D897-4302-BD4C-FC18F291ECB7@yesql.se

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/153836b99acb5c432b9e2326dbd75ac239f3c320

Modified Files
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.cirrus.tasks.yml | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)