[v1.10.0-beta3] Adhoc and postgres-continuous-discovery not work together. Credentials are missing

[chromko]

When we use together

• adhoc mode
• dbtype - postgres-continuous-discovery
• adhoc_conn_string

  env:
   ...
    - name: PW2_DATASTORE
      value: prometheus
    - name: PW2_ADHOC_DBTYPE
      value: postgres-continuous-discovery
    - name: PW2_ADHOC_NAME
      value: adhoc
    - name: PW2_ADHOC_CONFIG
      value: unprivileged
    - name: PW2_ADHOC_CONN_STR
       value: postgresql://user:password@localhost:5432/postgres

databases are discovered, but metrics cannot be scraped from them due to missing credentials. They're not propagated from PW2_ADHOC_CONN_STR.

In logs we can see something like

2023/01/13 11:34:20 INFO DBGetPGVersion: [adhoc_example2_db] DBGetPGVersion failed, using old cached value. err: dial tcp: lookup port=: no such host
2023/01/13 11:34:20 INFO DBGetPGVersion: [adhoc_exampl1e_db] DBGetPGVersion failed, using old cached value. err: dial tcp: lookup port=: no such host

That happens due'to no explicit credentials setting here