libpq: add 15.5

[Cogitri]

Specify library name and version: libpq/15.5

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• I've read the contributing guidelines.
• I've used a recent Conan client version close to the currently deployed.
• I've tried at least one configuration locally with the conan-center hook activated.

[conan-center-bot]

Conan v1 pipeline ✔️

All green in build 4 (358599a697169eab7ed03e65d8fc390d73784d37):

• libpq/15.5:
  All packages built successfully! (All logs)

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Conan v2 pipeline ✔️

Note: Conan v2 builds are now mandatory. Please read our discussion about it.

All green in build 3 (358599a697169eab7ed03e65d8fc390d73784d37):

• libpq/15.5:
  All packages built successfully! (All logs)

[ericLemanissierBot]

I detected other pull requests that are modifying libpq/all recipe:

• libpq: bump versions #21951

This message is automatically generated by https://github.com/ericLemanissier/conan-center-conflicting-prs so don't hesitate to report issues/improvements there.

[RubenRBS]

This PR did not get tagged internally so it was missed, sorry about that :(

[conan-center-bot]

This PR has been automatically merged due to Bump version or Bump dependencies label.
Read https://github.com/conan-io/conan-center-index/blob/master/docs/labels.md#bump-version to obtain more information.