build(deps): bump async-trait from 0.1.30 to 0.1.31

Bumps [async-trait](https://github.com/dtolnay/async-trait) from 0.1.30 to 0.1.31.
- [Release notes](https://github.com/dtolnay/async-trait/releases)
- [Commits](https://github.com/dtolnay/async-trait/compare/0.1.30...0.1.31)

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

Cargo.lock

@@ -15,7 +15,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "async-trait"
-version = "0.1.30"
+version = "0.1.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 1.0.12 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1259,7 +1259,7 @@ name = "tokio-postgres"
 version = "0.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "async-trait 0.1.30 (registry+https://github.com/rust-lang/crates.io-index)",
+ "async-trait 0.1.31 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "bytes 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "fallible-iterator 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1605,7 +1605,7 @@ dependencies = [
 [metadata]
 "checksum aho-corasick 0.7.10 (registry+https://github.com/rust-lang/crates.io-index)" = "8716408b8bc624ed7f65d223ddb9ac2d044c0547b6fa4b0d554f3a9540496ada"
 "checksum anyhow 1.0.29 (registry+https://github.com/rust-lang/crates.io-index)" = "dc98824304f5513bb8f862f9e5985219003de4d730689e59d8f28818283a6fe4"
-"checksum async-trait 0.1.30 (registry+https://github.com/rust-lang/crates.io-index)" = "da71fef07bc806586090247e971229289f64c210a278ee5ae419314eb386b31d"
+"checksum async-trait 0.1.31 (registry+https://github.com/rust-lang/crates.io-index)" = "26c4f3195085c36ea8d24d32b2f828d23296a9370a28aa39d111f6f16bef9f3b"
 "checksum atty 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)" = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
 "checksum autocfg 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f8aac770f1885fd7e387acedd76065302551364496e46b3dd00860b2f8359b9d"
 "checksum backtrace 0.3.46 (registry+https://github.com/rust-lang/crates.io-index)" = "b1e692897359247cc6bb902933361652380af0f1b7651ae5c5013407f30e109e"