[bitnami/sonarqube] Increase password length to minimum 12 characters

[migruiz4]

Description of the change

Increase random password length to avoid initialization issues:

sonarqube 11:28:01.81 INFO  ==> Configuring user credentials
{"result":"Password must be at least 12 characters long"}

Benefits

Fixes issues when sonarqubePassword is not set.

Checklist

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