The set route target does not seem to be used.
Sample config that will reproduce this behavior:
```
set interfaces bridge br0 enable-vlan
set interfaces bridge br0 member interface eth1.70
set interfaces bridge br0 member interface vxlan1
set interfaces dummy dum0 address '1.1.1.1/32'
set interfaces dummy dum2 address '10.0.255.1/32'
set interfaces ethernet eth1 address '192.168.10.2/31'
set interfaces ethernet eth1 vif 70
set interfaces ethernet eth2 address 'dhcp'
set interfaces ethernet eth2 hw-id '0c:73:b4:b6:00:02'
set interfaces loopback lo address '172.16.1.1/32'
set interfaces vxlan vxlan1 ip enable-arp-accept
set interfaces vxlan vxlan1 ip enable-arp-announce
set interfaces vxlan vxlan1 port '4789'
set interfaces vxlan vxlan1 source-address '10.0.255.1'
set interfaces vxlan vxlan1 source-interface 'dum2'
set interfaces vxlan vxlan1 vni '100070'
set protocols bgp address-family ipv4-unicast network 1.1.1.0/24
set protocols bgp address-family ipv4-unicast network 10.0.255.1/32
set protocols bgp address-family l2vpn-evpn advertise ipv4 unicast
set protocols bgp address-family l2vpn-evpn advertise-all-vni
set protocols bgp address-family l2vpn-evpn flooding
set protocols bgp address-family l2vpn-evpn vni 100070 advertise-default-gw
set protocols bgp address-family l2vpn-evpn vni 100070 rd '64999:100070'
set protocols bgp address-family l2vpn-evpn vni 100070 route-target both 70:100070
set protocols bgp neighbor 2.2.2.2 address-family l2vpn-evpn
set protocols bgp neighbor 2.2.2.2 bfd
set protocols bgp neighbor 2.2.2.2 ebgp-multihop '3'
set protocols bgp neighbor 2.2.2.2 remote-as '65001'
set protocols bgp neighbor 2.2.2.2 update-source '1.1.1.1'
set protocols bgp neighbor 192.168.10.3 address-family ipv4-unicast
set protocols bgp neighbor 192.168.10.3 bfd
set protocols bgp neighbor 192.168.10.3 remote-as '65001'
set protocols bgp system-as '1234'
```
The expected route-target would be 70:100070. But the real route-target is 15645:100070
```
vyos@vyos:~$ show bgp l2vpn evpn
BGP table version is 2, local router ID is 172.16.1.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete
EVPN type-1 prefix: [1]:[EthTag]:[ESI]:[IPlen]:[VTEP-IP]:[Frag-id]
EVPN type-2 prefix: [2]:[EthTag]:[MAClen]:[MAC]:[IPlen]:[IP]
EVPN type-3 prefix: [3]:[EthTag]:[IPlen]:[OrigIP]
EVPN type-4 prefix: [4]:[ESI]:[IPlen]:[OrigIP]
EVPN type-5 prefix: [5]:[EthTag]:[IPlen]:[IP]
Network Next Hop Metric LocPrf Weight Path
Route Distinguisher: 64999:100070
*> [3]:[0]:[32]:[10.0.255.1]
10.0.255.1 32768 i
ET:8 RT:15645:100070
Displayed 1 out of 1 total prefixes
```
VyOS version info:
```
vyos@vyos:~$ sh ver
Version: VyOS 1.4-rolling-202302080317
Release train: current
Built by:
[email protected]
Built on: Wed 08 Feb 2023 03:17 UTC
Build UUID: ce4d9361-2f83-44a1-88f4-488f1aa20f02
Build commit ID: 8cade9112a16ed
Architecture: x86_64
Boot via: installed image
System type: KVM guest
Hardware vendor: QEMU
Hardware model: Standard PC (i440FX + PIIX, 1996)
Hardware S/N:
Hardware UUID: 4773b4b6-6bb8-46aa-85b9-4e4cf6d533ad
Copyright: VyOS maintainers and contributors
vyos@vyos:~$
```