Settings service: 2 envvars needed to be added to existin ones

[mmattel]

Identified while reading: #9490 (set the configured protocol transport for service metadata)

The settings service has two envvars that do not start with SETTINGS_ but with STORAGE_. These envvars are unfindable because there is no storage service. The envvars in question are:

STORAGE_GRPC_ADDR and
STORAGE_GATEWAY_GRPC_ADDR

To fix this, we should ADD correct named envvars to the existing ones:

SETTINGS_STORAGE_GRPC_ADDR and
SETTINGS_STORAGE_GATEWAY_GRPC_ADDR

Of course deprecating the "wrong" named one is appreciated, technically there is no hard need for it.

@dragonchaser @kobergj @butonic

[butonic]

damn

// Metadata configures the metadata store to use
type Metadata struct {
	GatewayAddress string `yaml:"gateway_addr" env:"STORAGE_GATEWAY_GRPC_ADDR" desc:"GRPC address of the STORAGE-SYSTEM service." introductionVersion:"pre5.0"`
	StorageAddress string `yaml:"storage_addr" env:"STORAGE_GRPC_ADDR" desc:"GRPC address of the STORAGE-SYSTEM service." introductionVersion:"pre5.0"`

Yeah ... that should be

// Metadata configures the metadata store to use
type Metadata struct {
	GatewayAddress string `yaml:"gateway_addr" env:"SETTINGS_STORAGE_GATEWAY_GRPC_ADDR" desc:"GRPC address of the STORAGE-SYSTEM service." introductionVersion:"pre5.0"`
	StorageAddress string `yaml:"storage_addr" env:"SETTINGS_STORAGE_GRPC_ADDR" desc:"GRPC address of the STORAGE-SYSTEM service." introductionVersion:"pre5.0"`

introduced pre 5.0 ... we should at least add the SETTINGS_ prefixed env vars ... @mmattel care to prepare a PR?