Bump alpine from 51b6726 to 77726ef in /integration-test (#600)

Bumps alpine from `51b6726` to `77726ef`.

---
updated-dependencies:
- dependency-name: alpine
  dependency-type: direct:production
...

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

integration-test/Dockerfile.tester

@@ -1,4 +1,4 @@
-FROM alpine@sha256:51b67269f354137895d43f3b3d810bfacd3945438e94dc5ac55fdac340352f48
+FROM alpine@sha256:77726ef6b57ddf65bb551896826ec38bc3e53f75cdde31354fbffb4f25238ebd
 
 USER root