MySQL statefulset deployment with persitence volume not working - mysql

Question

Environment :
Using Helm v3 charts for deployment.
Using Bitnami MySQL charts from the following source : https://artifacthub.io/packages/helm/bitnami/mysql
Username and Password is generated randomly for every deployment.
PersistenceVolume is created of type "standard" storage class.
Entire k8 cluster is done on Baremetal.
When deploying for the first time, installation goes successfully, all the mysql db files get generated appropriately in the data directory. After doing uninstall and then doing the install does not work, because the mysql data directory has db and config files for previously generated credentials.
As of now, after doing uninstall, we are manually clearing the files from the node before installing.
Looking forward on how to :
Clearing only the config files and keeping the db files intact.
On deleting persistent volume, clear all the files from the data directory.
Alter the DB with new username and password to use existing files as it is.
Persistence Volume K8 yaml
kind: PersistentVolume
apiVersion: v1
metadata:
name: mysql-pv
labels:
type: local
name: mysql-pv
spec:
storageClassName: standard
capacity:
storage: 2Gi
accessModes:
- ReadWriteOnce
hostPath:
path: "/tmp/"
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: mysql-pvc
labels:
name: mysql-pvc
spec:
accessModes:
- ReadWriteOnce
volumeMode: Filesystem
resources:
requests:
storage: 2Gi
selector:
matchLabels:
name: mysql-pv