deps: update docker.io/library/maven:3.9.9-eclipse-temurin-11-alpine docker digest to 456f60c (#3607)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| docker.io/library/maven | stage | digest | `d323c2b` -> `456f60c` |

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Author: renovate-bot

.cloudbuild/library_generation/library_generation.Dockerfile

@@ -15,7 +15,7 @@
 # install gapic-generator-java in a separate layer so we don't overload the image
 # with the transferred source code and jars
 
-FROM docker.io/library/maven:3.9.9-eclipse-temurin-11-alpine@sha256:d323c2bf4d095c661930481ad2179d41aa3a5b807c7bf9f4cb15ed331fc6997a AS ggj-build
+FROM docker.io/library/maven:3.9.9-eclipse-temurin-11-alpine@sha256:456f60c1643cf70e3c1d630884387fbfa207ad5975d17b0323cc36030dc13c40 AS ggj-build
 
 WORKDIR /sdk-platform-java
 COPY . .