build(deps): bump github.com/jackc/pgx/v4 from 4.13.0 to 4.15.0

Bumps [github.com/jackc/pgx/v4](https://github.com/jackc/pgx) from 4.13.0 to 4.15.0.
- [Release notes](https://github.com/jackc/pgx/releases)
- [Changelog](https://github.com/jackc/pgx/blob/master/CHANGELOG.md)
- [Commits](https://github.com/jackc/pgx/compare/v4.13.0...v4.15.0)

---
updated-dependencies:
- dependency-name: github.com/jackc/pgx/v4
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/github.com/jackc/puddle/CHANGELOG.md

@@ -1,3 +1,17 @@
+# 1.2.1 (December 2, 2021)
+
+* TryAcquire now does not block when background constructing resource
+
+# 1.2.0 (November 20, 2021)
+
+* Add TryAcquire (A. Jensen)
+* Fix: remove memory leak / unintentionally pinned memory when shrinking slices (Alexander Staubo)
+* Fix: Do not leave pool locked after panic from nil context
+
+# 1.1.4 (September 11, 2021)
+
+* Fix: Deadlock in CreateResource if pool was closed during resource acquisition (Dmitriy Matrenichev)
+
 # 1.1.3 (December 3, 2020)
 
 * Fix: Failed resource creation could cause concurrent Acquire to hang. (Evgeny Vanslov)