Bump azul/zulu-openjdk-alpine in /api

Bumps azul/zulu-openjdk-alpine from 21.0.5-jre-headless to 21.0.6-jre-headless.

---
updated-dependencies:
- dependency-name: azul/zulu-openjdk-alpine
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

api/Dockerfile

@@ -1,7 +1,7 @@
 # The tag is ignored when a sha is included but the reason to add it are:
 # 1. Self Documentation: It is difficult to find out what the expected tag is given a sha alone
 # 2. Helps dependabot during discovery of upgrades
-FROM azul/zulu-openjdk-alpine:21.0.6-jre-headless@sha256:472c058d73210246e8082321a2dd44df672647839a8e22c230200eef8549f9ea
+FROM azul/zulu-openjdk-alpine:21.0.6-jre-headless@sha256:75c5cc1ca1429513b56e9cbe3121bce86476cdec18b5b74b6842ab0af4b5a57f
 
 RUN apk add --no-cache \
     # snappy codec