build(deps): bump github.com/jackc/pgx/v4 in /backend

Bumps [github.com/jackc/pgx/v4](https://github.com/jackc/pgx) from 4.18.2 to 4.18.3.
- [Changelog](https://github.com/jackc/pgx/blob/v4.18.3/CHANGELOG.md)
- [Commits](jackc/pgx@v4.18.2...v4.18.3)

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

Signed-off-by: dependabot[bot] <[email protected]>

backend/go.mod

@@ -12,7 +12,7 @@ require (
 	github.com/google/go-github/v28 v28.1.1
 	github.com/google/uuid v1.6.0
 	github.com/gorilla/securecookie v1.1.2
-	github.com/jackc/pgx/v4 v4.18.2
+	github.com/jackc/pgx/v4 v4.18.3
 	github.com/jinzhu/copier v0.4.0
 	github.com/jmoiron/sqlx v1.3.5
 	github.com/kevinburke/go-bindata v3.24.0+incompatible

backend/go.sum

@@ -465,8 +465,8 @@ github.com/jackc/pgx/v4 v4.0.0-20190420224344-cc3461e65d96/go.mod h1:mdxmSJJuR08
 github.com/jackc/pgx/v4 v4.0.0-20190421002000-1b8f0016e912/go.mod h1:no/Y67Jkk/9WuGR0JG/JseM9irFbnEPbuWV2EELPNuM=
 github.com/jackc/pgx/v4 v4.0.0-pre1.0.20190824185557-6972a5742186/go.mod h1:X+GQnOEnf1dqHGpw7JmHqHc1NxDoalibchSk9/RWuDc=
 github.com/jackc/pgx/v4 v4.12.1-0.20210724153913-640aa07df17c/go.mod h1:1QD0+tgSXP7iUjYm9C1NxKhny7lq6ee99u/z+IHFcgs=
-github.com/jackc/pgx/v4 v4.18.2 h1:xVpYkNR5pk5bMCZGfClbO962UIqVABcAGt7ha1s/FeU=
-github.com/jackc/pgx/v4 v4.18.2/go.mod h1:Ey4Oru5tH5sB6tV7hDmfWFahwF15Eb7DNXlRKx2CkVw=
+github.com/jackc/pgx/v4 v4.18.3 h1:dE2/TrEsGX3RBprb3qryqSV9Y60iZN1C6i8IrmW9/BA=
+github.com/jackc/pgx/v4 v4.18.3/go.mod h1:Ey4Oru5tH5sB6tV7hDmfWFahwF15Eb7DNXlRKx2CkVw=
 github.com/jackc/puddle v0.0.0-20190413234325-e4ced69a3a2b/go.mod h1:m4B5Dj62Y0fbyuIc15OsIqK0+JU8nkqQjsgx7dvjSWk=
 github.com/jackc/puddle v0.0.0-20190608224051-11cab39313c9/go.mod h1:m4B5Dj62Y0fbyuIc15OsIqK0+JU8nkqQjsgx7dvjSWk=
 github.com/jackc/puddle v1.1.3/go.mod h1:m4B5Dj62Y0fbyuIc15OsIqK0+JU8nkqQjsgx7dvjSWk=