[vault] metrics name of secret engine

[phac008]

Vault use secret engines as metrics names -> due to character conversation (- to _) some of grafana dashboard functions are not working properly...

there was a change request some time ago:
hashicorp/vault#9068

currently i try to investigate if this could be solved with variable conversion in grafana ....
alternative: make specifications that secrets must only consist of [a-zA-Z0-9]_

[phac008]

solved for my case with label_replace - must not be valid in some other cases with more dashes or other special characters:

https://github.com/suxess-it/sx-cnp-oss/blob/22c4dbd67d7c8289eeeb93190d016bf95c5fcdd6/platform-apps/charts/vault/dashboard-files/vault-dashboard.json#L4601