cargo: update diesel, pq-sys (#10256)

## Problem

Versions of `diesel` and `pq-sys` were somewhat stale. I was checking on
libpq->openssl versions while investigating a segfault via
https://github.com/neondatabase/cloud/issues/21010. I don't think these
rust bindings are likely to be the source of issues, but we might as
well freshen them as a precaution.

## Summary of changes

- Update diesel to 2.2.6
- Update pq-sys to 0.6.3

Cargo.lock

@@ -1733,9 +1733,9 @@ checksum = "ab03c107fafeb3ee9f5925686dbb7a73bc76e3932abb0d2b365cb64b169cf04c"
 
 [[package]]
 name = "diesel"
-version = "2.2.3"
+version = "2.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "65e13bab2796f412722112327f3e575601a3e9cdcbe426f0d30dbf43f3f5dc71"
+checksum = "ccf1bedf64cdb9643204a36dd15b19a6ce8e7aa7f7b105868e9f1fad5ffa7d12"
 dependencies = [
  "bitflags 2.4.1",
  "byteorder",
@@ -4494,9 +4494,9 @@ checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
 
 [[package]]
 name = "pq-sys"
-version = "0.4.8"
+version = "0.6.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "31c0052426df997c0cbd30789eb44ca097e3541717a7b8fa36b1c464ee7edebd"
+checksum = "f6cc05d7ea95200187117196eee9edd0644424911821aeb28a18ce60ea0b8793"
 dependencies = [
  "vcpkg",
 ]

storage_controller/Cargo.toml

@@ -43,13 +43,13 @@ scopeguard.workspace = true
 strum.workspace = true
 strum_macros.workspace = true
 
-diesel = { version = "2.1.4", features = [
+diesel = { version = "2.2.6", features = [
     "serde_json",
     "postgres",
     "r2d2",
     "chrono",
 ] }
-diesel_migrations = { version = "2.1.0" }
+diesel_migrations = { version = "2.2.0" }
 r2d2 = { version = "0.8.10" }
 
 utils = { path = "../libs/utils/" }