fix(deps): update module github.com/cenkalti/backoff/v4 to v5

Author: renovate[bot]

go.mod

@@ -3,7 +3,7 @@ module github.com/int128/kauthproxy
 go 1.23.5
 
 require (
-	github.com/cenkalti/backoff/v4 v4.3.0
+	github.com/cenkalti/backoff/v5 v5.0.1
 	github.com/chromedp/chromedp v0.12.1
 	github.com/google/wire v0.6.0
 	github.com/int128/listener v1.2.0

go.sum

@@ -6,8 +6,8 @@ github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5 h1:0CwZNZbxp69SHPd
 github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5/go.mod h1:wHh0iHkYZB8zMSxRWpUBQtwG5a7fFgvEO+odwuTv2gs=
 github.com/blang/semver/v4 v4.0.0 h1:1PFHFE6yCCTv8C1TeyNNarDzntLi7wMI5i/pzqYIsAM=
 github.com/blang/semver/v4 v4.0.0/go.mod h1:IbckMUScFkM3pff0VJDNKRiT6TG/YpiHIM2yvyW5YoQ=
-github.com/cenkalti/backoff/v4 v4.3.0 h1:MyRJ/UdXutAwSAT+s3wNd7MfTIcy71VQueUuFK343L8=
-github.com/cenkalti/backoff/v4 v4.3.0/go.mod h1:Y3VNntkOUPxTVeUxJ/G5vcM//AlwfmyYozVcomhLiZE=
+github.com/cenkalti/backoff/v5 v5.0.1 h1:kGZdCHH1+eW+Yd0wftimjMuhg9zidDvNF5aGdnkkb+U=
+github.com/cenkalti/backoff/v5 v5.0.1/go.mod h1:rkhZdG3JZukswDf7f0cwqPNk4K0sa+F97BxZthm/crw=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/chromedp/cdproto v0.0.0-20250120090109-d38428e4d9c8 h1:Q2byC+xLgH/Z7hExJ8G/jVqsvCfGhMmNgM1ysZARA3o=
 github.com/chromedp/cdproto v0.0.0-20250120090109-d38428e4d9c8/go.mod h1:RTGuBeCeabAJGi3OZf71a6cGa7oYBfBP75VJZFLv6SU=

internal/authproxy/auth_proxy.go

@@ -8,7 +8,7 @@ import (
 	"strings"
 	"sync"
 
-	"github.com/cenkalti/backoff/v4"
+	"github.com/cenkalti/backoff/v5"
 	"github.com/google/wire"
 	"github.com/int128/kauthproxy/internal/browser"
 	"github.com/int128/kauthproxy/internal/env"