Keep the default LB strategy if an invalid p* one is used

.ci/test2-dnscrypt-proxy.toml

@@ -4,6 +4,7 @@ require_dnssec = true
 dnscrypt_ephemeral_keys = true
 tls_disable_session_tickets = false
 ignore_system_dns = false
+lb_strategy = 'p12'
 block_ipv6 = true
 block_unqualified = true
 block_undelegated = true

dnscrypt-proxy/config.go

@@ -375,9 +375,10 @@ func ConfigLoad(proxy *Proxy, flags *ConfigFlags) error {
 		if strings.HasPrefix(lbStrategyStr, "p") {
 			n, err := strconv.ParseInt(strings.TrimPrefix(lbStrategyStr, "p"), 10, 32)
 			if err != nil || n <= 0 {
-				dlog.Fatalf("Invalid load balancing strategy: [%s]", config.LBStrategy)
+				dlog.Warnf("Invalid load balancing strategy: [%s]", config.LBStrategy)
+			} else {
+				lbStrategy = LBStrategyPN{n: int(n)}
 			}
-			lbStrategy = LBStrategyPN{n: int(n)}
 		} else {
 			dlog.Warnf("Unknown load balancing strategy: [%s]", config.LBStrategy)
 		}