Fix a syntax error in peerdb template

[mkaze]

Those extra parentheses for and causes the following error:

Error: template: peerdb/templates/peerdb-server-ui-secret.yaml:1:24: executing "peerdb/templates/peerdb-server-ui-secret.yaml" at <.Values.peerdbUI.credentials.passwordExistingSecret>: passwordExistingSecret is not a method but has arguments

Checklist:

• Bumped the chart version(s) according to semantic versioning
  • Bump up both peerdb and peerdb-catalog charts to the same version
• Update peerdb-catalog/values.yaml:
  • Set temporal.admintools.image.tag pointing to version with correct value from the dependency in peerdb/Chart.yaml subdependency

[CLAassistant]

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