avoid passing hardcoded db credentials to flower

[MoralCode]

flower currently depends on hardcoded credentials

augur-on-ocp/bases/augur/flower/flower-deployment.yaml

Line 21 in a121ed2

value: "postgresql+psycopg2://augur:augur@augur-db:5432/augur" # pragma: allowlist secret

This is because we arent able to pass in the DB connection parameters as individual variables, as the crunchy postgres operator is designed to do (and indeed does do for the other parts of the stack, such as augur itself)

We should find a way to fix this