add more configuration descriptions

extensions/search/pkg/config/config.go

@@ -22,7 +22,7 @@ type Config struct {
 	Reva     Reva   `yaml:"reva"`
 	Events   Events `yaml:"events"`
 
-	MachineAuthAPIKey string `yaml:"machine_auth_api_key" env:"OCIS_MACHINE_AUTH_API_KEY;SEARCH_MACHINE_AUTH_API_KEY"`
+	MachineAuthAPIKey string `yaml:"machine_auth_api_key" env:"OCIS_MACHINE_AUTH_API_KEY;SEARCH_MACHINE_AUTH_API_KEY" desc: "Machine auth API key used for accessing the 'auth-machine' service to impersonate users."`
 
 	Context context.Context `yaml:"-"`
 }

extensions/search/pkg/config/reva.go

@@ -2,5 +2,5 @@ package config
 
 // Reva defines all available REVA configuration.
 type Reva struct {
-	Address string `ocisConfig:"address" env:"REVA_GATEWAY" desc:"The CS3 gateway endpoint"`
+	Address string `ocisConfig:"address" env:"REVA_GATEWAY" desc:"The CS3 gateway endpoint."`
 }