Bump github.com/gofiber/fiber/v2 from 2.49.2 to 2.50.0 in /backend

Bumps [github.com/gofiber/fiber/v2](https://github.com/gofiber/fiber) from 2.49.2 to 2.50.0.
- [Release notes](https://github.com/gofiber/fiber/releases)
- [Commits](https://github.com/gofiber/fiber/compare/v2.49.2...v2.50.0)

---
updated-dependencies:
- dependency-name: github.com/gofiber/fiber/v2
  dependency-type: direct:production
...

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

backend/go.mod

@@ -5,7 +5,7 @@ go 1.20
 require (
 	github.com/goccy/go-json v0.10.2
 	github.com/gofiber/contrib/websocket v1.2.0
-	github.com/gofiber/fiber/v2 v2.49.2
+	github.com/gofiber/fiber/v2 v2.50.0
 	github.com/rs/zerolog v1.30.0
 	github.com/snakesel/libretranslate v0.0.2
 	github.com/wader/goutubedl v0.0.0-20230817095831-89e825670ccd
@@ -26,7 +26,7 @@ require (
 	github.com/rivo/uniseg v0.2.0 // indirect
 	github.com/savsgio/gotils v0.0.0-20230208104028-c358bd845dee // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect
-	github.com/valyala/fasthttp v1.49.0 // indirect
+	github.com/valyala/fasthttp v1.50.0 // indirect
 	github.com/valyala/tcplisten v1.0.0 // indirect
 	github.com/xdg-go/pbkdf2 v1.0.0 // indirect
 	github.com/xdg-go/scram v1.1.2 // indirect
@@ -34,7 +34,7 @@ require (
 	github.com/youmark/pkcs8 v0.0.0-20181117223130-1be2e3e5546d // indirect
 	golang.org/x/crypto v0.7.0 // indirect
 	golang.org/x/sync v0.1.0 // indirect
-	golang.org/x/sys v0.12.0 // indirect
+	golang.org/x/sys v0.13.0 // indirect
 	golang.org/x/text v0.8.0 // indirect
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 )