[chore]: Bump github.com/jackc/pgx/v4 from 4.17.2 to 4.18.1 (#1595)

Bumps [github.com/jackc/pgx/v4](https://github.com/jackc/pgx) from 4.17.2 to 4.18.1.
- [Release notes](https://github.com/jackc/pgx/releases)
- [Changelog](https://github.com/jackc/pgx/blob/v4.18.1/CHANGELOG.md)
- [Commits](https://github.com/jackc/pgx/compare/v4.17.2...v4.18.1)

---
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>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

vendor/github.com/jackc/pgproto3/v2/README.md

@@ -1,6 +1,12 @@
 [![](https://godoc.org/github.com/jackc/pgproto3?status.svg)](https://godoc.org/github.com/jackc/pgproto3)
 [![Build Status](https://travis-ci.org/jackc/pgproto3.svg)](https://travis-ci.org/jackc/pgproto3)
 
+---
+
+This version is used with pgx `v4`. In pgx `v5` it is part of the https://github.com/jackc/pgx repository.
+
+---
+
 # pgproto3
 
 Package pgproto3 is a encoder and decoder of the PostgreSQL wire protocol version 3.

vendor/github.com/jackc/pgproto3/v2/sasl_initial_response.go

@@ -2,7 +2,6 @@ package pgproto3
 
 import (
 	"bytes"
-	"encoding/hex"
 	"encoding/json"
 	"errors"
 
@@ -83,12 +82,6 @@ func (dst *SASLInitialResponse) UnmarshalJSON(data []byte) error {
 		return err
 	}
 	dst.AuthMechanism = msg.AuthMechanism
-	if msg.Data != "" {
-		decoded, err := hex.DecodeString(msg.Data)
-		if err != nil {
-			return err
-		}
-		dst.Data = decoded
-	}
+	dst.Data = []byte(msg.Data)
 	return nil
 }

vendor/github.com/jackc/pgproto3/v2/sasl_response.go

@@ -1,7 +1,6 @@
 package pgproto3
 
 import (
-	"encoding/hex"
 	"encoding/json"
 
 	"github.com/jackc/pgio"
@@ -50,12 +49,6 @@ func (dst *SASLResponse) UnmarshalJSON(data []byte) error {
 	if err := json.Unmarshal(data, &msg); err != nil {
 		return err
 	}
-	if msg.Data != "" {
-		decoded, err := hex.DecodeString(msg.Data)
-		if err != nil {
-			return err
-		}
-		dst.Data = decoded
-	}
+	dst.Data = []byte(msg.Data)
 	return nil
 }