deps: update docker.io/library/alpine:3.20.3 docker digest to 1e42bbe (#3417)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| docker.io/library/alpine | stage | digest | `beefdbd` -> `1e42bbe` |

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Author: renovate-bot

.cloudbuild/library_generation/library_generation.Dockerfile

@@ -27,7 +27,7 @@ RUN mvn install -B -ntp -DskipTests -Dclirr.skip -Dcheckstyle.skip
 RUN cp "/root/.m2/repository/com/google/api/gapic-generator-java/${DOCKER_GAPIC_GENERATOR_VERSION}/gapic-generator-java-${DOCKER_GAPIC_GENERATOR_VERSION}.jar" \
   "./gapic-generator-java.jar"
 
-FROM docker.io/library/alpine:3.20.3@sha256:beefdbd8a1da6d2915566fde36db9db0b524eb737fc57cd1367effd16dc0d06d as glibc-compat
+FROM docker.io/library/alpine:3.20.3@sha256:1e42bbe2508154c9126d48c2b8a75420c3544343bf86fd041fb7527e017a4b4a as glibc-compat
 
 RUN apk add git sudo
 # This SHA is the latest known-to-work version of this binary compatibility tool