[bitnami/postgresql-ha] Fix port used for ingress traffic on pgpool network policy

[renemeye]

Description of the change

The value that had been used for ingress traffic Values.pgpool.containerPorts.pgpool is not defined in values. It rather should be Values.pgpool.containerPorts.postgresql

Benefits

Possible drawbacks

Applicable issues

Additional information

Checklist

• [X] Chart version bumped in Chart.yaml according to semver. This is not necessary when the changes only affect README.md files.
• [X] Title of the pull request follows this pattern [bitnami/<name_of_the_chart>] Descriptive title
• [X] All commits signed off and in agreement of Developer Certificate of Origin (DCO)