cmd, metrics: add support for influxdb-v2 (cherry-picking from italoacasas' changes), leave existing support for v1 to maintain backwards-compatibility. (#23194)

This PR adds flag to enable InfluxDB v2 (--metrics.influxdbv2), flags for v2-specific features (--metrics.influxdb.token, --metrics.influxdb.bucket), also carries over addition of support for specifying organization (--metrics.influxdb.organization), but still retains backwards compatibility with InfluxDB v1.

metrics/config.go

@@ -28,6 +28,11 @@ type Config struct {
 	InfluxDBUsername string `toml:",omitempty"`
 	InfluxDBPassword string `toml:",omitempty"`
 	InfluxDBTags     string `toml:",omitempty"`
+
+	EnableInfluxDBV2     bool   `toml:",omitempty"`
+	InfluxDBToken        string `toml:",omitempty"`
+	InfluxDBBucket       string `toml:",omitempty"`
+	InfluxDBOrganization string `toml:",omitempty"`
 }
 
 // DefaultConfig is the default config for metrics used in go-ethereum.
@@ -42,4 +47,10 @@ var DefaultConfig = Config{
 	InfluxDBUsername: "test",
 	InfluxDBPassword: "test",
 	InfluxDBTags:     "host=localhost",
+
+	// influxdbv2-specific flags
+	EnableInfluxDBV2:     false,
+	InfluxDBToken:        "test",
+	InfluxDBBucket:       "geth",
+	InfluxDBOrganization: "geth",
 }