fix extraconfig-from-values.hcl condition mismatch

[nicholas-weidmann]

when setting the following values it's possible to disable the extraconfigs, which was my goal. But the conditions are mismatched and the cp command from vault.args fails on container start.

vault:
  server:
    standalone:
      config: ""
    ha:
      config: ""
      raft:
        config: ""

[hashicorp-cla-app]

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