Tentatively fixes connectivity and tunnel start issues (#875)

Task/Issue URL: https://app.asana.com/0/0/1207717985731035/f

iOS PR: duckduckgo/iOS#3027
macOS PR: duckduckgo/macos-browser#2933

What kind of version bump will this require?: Patch

## Description

This PR tries to fix a VPN extension crash and some potential connectivity issues.

Sources/NetworkProtection/PacketTunnelProvider.swift

@@ -603,7 +603,7 @@ open class PacketTunnelProvider: NEPacketTunnelProvider {
                 // expired.  In either case it should be enough to record the manual failures
                 // for these prerequisited to avoid flooding our metrics.
                 providerEvents.fire(.tunnelStartOnDemandWithoutAccessToken)
-                try? await Task.sleep(interval: .seconds(15))
+                try await Task.sleep(interval: .seconds(15))
             } else {
                 // If the VPN was started manually without the basic prerequisites we always
                 // want to know as this should not be possible.
@@ -631,7 +631,7 @@ open class PacketTunnelProvider: NEPacketTunnelProvider {
                 // We add a delay when the VPN is started by
                 // on-demand and there's an error, to avoid frenetic ON/OFF
                 // cycling.
-                try? await Task.sleep(interval: .seconds(15))
+                try await Task.sleep(interval: .seconds(15))
             }
 
             let errorDescription = (error as? LocalizedError)?.localizedDescription ?? String(describing: error)
@@ -1297,13 +1297,6 @@ open class PacketTunnelProvider: NEPacketTunnelProvider {
             connectionStatus = .connected(connectedDate: Date())
         }
 
-        if !settings.disableRekeying {
-            guard !isKeyExpired else {
-                try await rekey()
-                return
-            }
-        }
-
         os_log("🔵 Tunnel interface is %{public}@", log: .networkProtection, type: .info, adapter.interfaceName ?? "unknown")
 
         // These cases only make sense in the context of a connection that had trouble