Fix serviceAccountName not being set when create=false

[eskp]

Problem

Deployments using serviceAccount.create: false with an existing service account name were incorrectly using the default service account instead of the specified one.

Root Cause

Two bugs in the common chart:

1. _helpers.tpl - common.serviceAccountName helper used .Values.service.name instead of .Values.serviceAccount.name

2. deployment.yaml - Only set serviceAccountName when serviceAccount.create was true:

   {{- if .Values.serviceAccount.create }}
   serviceAccountName: {{ include "common.serviceAccountName" . }}
   {{- end }}

Fix

1. Fixed helper to use correct path: .Values.serviceAccount.name
2. Changed condition to check serviceAccount.name instead of serviceAccount.create

Now serviceAccountName is set whenever a name is provided, regardless of whether the chart creates the SA or uses an existing one.

Test Plan

• Deploy with serviceAccount.create: true → SA created and used
• Deploy with serviceAccount.create: false, name: existing-sa → existing SA used

[github-actions]

🎉 Helm Chart Tests Passed!

All modified charts have been successfully validated:

Chart	Version Check	Template Validation	Dry-run Installation	Overall Status
common	✅ Incremented	✅ Passed	✅ Passed	✅ Passed

Summary:

• ✅ Charts tested: common
• ✅ All template validations passed
• ✅ All dry-run installations passed

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The PR is ready for review! 🚀

Note: Charts will be automatically released when this PR is merged to main.