Alerting: Update grafana/alerting from de176b4a0309 to 83b6de6b0a35 (#105157)

* Update grafana alerting from de176b4a0309 to 83b6de6b0a35

Includes:
- https://github.com/grafana/alerting/pull/319
- https://github.com/grafana/alerting/pull/317

* Remove unused SendWebhook method from sender struct

grafana/alerting hasn't used the grafana webhook sender for a while now,
so this method is no longer used anywhere.

- Removed SendWebhook from the sender struct and rename it to emailSender
so that its use is clearer.
- Also, for similar reasons, the Webhook method on Grafana's
webhook sender `sendWebRequestSync` should not call grafana/alerting code for
NewTLSClient. The previous grafana/alerting function is vendored into grafana.

* Use BuildReceiverIntegrations new func signature

pkg/services/notifications/webhook.go

@@ -7,10 +7,10 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"net"
 	"net/http"
 	"net/url"
-
-	alertingHTTP "github.com/grafana/alerting/http"
+	"time"
 
 	"github.com/grafana/grafana/pkg/util"
 )
@@ -71,7 +71,7 @@ func (ns *NotificationService) sendWebRequestSync(ctx context.Context, webhook *
 		request.Header.Set(k, v)
 	}
 
-	resp, err := alertingHTTP.NewTLSClient(webhook.TLSConfig).Do(request)
+	resp, err := NewTLSClient(webhook.TLSConfig).Do(request)
 	if err != nil {
 		return redactURL(err)
 	}
@@ -111,3 +111,26 @@ func redactURL(err error) error {
 	e.URL = "<redacted>"
 	return e
 }
+
+// NewTLSClient creates a new HTTP client with the provided TLS configuration or with default settings.
+func NewTLSClient(tlsConfig *tls.Config) *http.Client {
+	nc := func(tlsConfig *tls.Config) *http.Client {
+		return &http.Client{
+			Timeout: time.Second * 30,
+			Transport: &http.Transport{
+				TLSClientConfig: tlsConfig,
+				Proxy:           http.ProxyFromEnvironment,
+				Dial: (&net.Dialer{
+					Timeout: 30 * time.Second,
+				}).Dial,
+				TLSHandshakeTimeout: 5 * time.Second,
+			},
+		}
+	}
+
+	if tlsConfig == nil {
+		return nc(&tls.Config{Renegotiation: tls.RenegotiateFreelyAsClient})
+	}
+
+	return nc(tlsConfig)
+}