feat: fill more http transport parameters in inputs/burrow plugin

Default http.Transport doesn't setup dial timeout.
That leads to client stuck if for some reason there's no working
DNS or if server client connects to is stuck.

Explicitly configure dialer and other parameters.

plugins/inputs/burrow/burrow.go

@@ -3,6 +3,7 @@ package burrow
 import (
 	"encoding/json"
 	"fmt"
+	"net"
 	"net/http"
 	"net/url"
 	"strconv"
@@ -218,11 +219,21 @@ func (b *burrow) createClient() (*http.Client, error) {
 		return nil, err
 	}
 
+	var transport http.Transport
+	timeout := time.Duration(b.ResponseTimeout)
+	transport.DialContext = (&net.Dialer{
+		Timeout: timeout,
+		DualStack: true,
+	}).DialContext
+	transport.TLSClientConfig = tlsCfg
+	transport.MaxIdleConnsPerHost = b.ConcurrentConnections / 2
+	transport.MaxConnsPerHost = b.ConcurrentConnections
+	transport.ResponseHeaderTimeout = timeout
+	transport.IdleConnTimeout = 90*time.Second
+
 	client := &http.Client{
-		Transport: &http.Transport{
-			TLSClientConfig: tlsCfg,
-		},
-		Timeout: time.Duration(b.ResponseTimeout),
+		Transport: &transport,
+		Timeout: timeout,
 	}
 
 	return client, nil