helm: fix bucket hook treating an existing bucket as missing (#11982)

* helm: fix bucket hook treating an existing bucket as missing

The skip check pipes awk into `grep -q`, which exits on the first match and
can leave awk writing into a closed pipe. awk then dies of SIGPIPE and
`set -o pipefail` makes the pipeline report that, so a bucket that exists
reads as missing: the hook runs `s3.bucket.create`, it errors with "already
exists", and `sh -ec` aborts the hook - failing the release.

Match in a single awk instead, which reads to EOF and cannot be killed by a
closing reader.

* helm: force string compare in bucket hook existence check

---------

Co-authored-by: Chris Lu <chris.lu@gmail.com>

k8s/charts/seaweedfs/templates/shared/post-install-bucket-hook.yaml

@@ -172,7 +172,8 @@ spec:
             {{- $bucketName := .name }}
             {{- $bucketLock := or .lock .objectLock .withLock }}
             bucket_list=$(/bin/echo 's3.bucket.list' | /usr/bin/weed shell) || { echo "Error listing s3 buckets"; exit 1; }
-            if echo "$bucket_list" | awk '{print $1}' | grep -Fxq "{{ $bucketName }}"; then
+            {{- /* One awk: grep -q exits early, awk takes SIGPIPE, pipefail fails the test. */}}
+            if printf '%s\n' "$bucket_list" | awk -v bucket="{{ $bucketName }}" '$1 "" == bucket { found = 1 } END { exit !found }'; then
               echo "Bucket '{{ $bucketName }}' already exists, skipping creation."
             else
               echo "Creating bucket '{{ $bucketName }}'..."