chore(deps): bump golang from `5f68ec6` to `b305420` in /e2e (#6539)

Bumps golang from `5f68ec6` to `b305420`.

---
updated-dependencies:
- dependency-name: golang
  dependency-version: 1.26.4-bookworm
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

e2e/Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.26.4-bookworm@sha256:5f68ec6805843bd3981a951ffada82a26a0bd2631045c8f7dba483fa868f5ec5 AS builder
+FROM golang:1.26.4-bookworm@sha256:b305420a68d0f229d91eb3b3ed9e519fcf2cf5461da4bef997bf927e8c0bfd2b AS builder
 RUN go install github.com/onsi/ginkgo/v2/ginkgo@v2.1.6
 
 FROM alpine:3.24.1@sha256:28bd5fe8b56d1bd048e5babf5b10710ebe0bae67db86916198a6eec434943f8b