tools: fix frr-reload for nbr deletion

tools: fix frr-reload for nbr deletion

bgp neighbor config can have multiple lines, if neighbor is
deleted via frr-reload, no neighbor remote-as <> wipes out
the neighbor, subsequent neighbor associated config deletion
would throw generic error.
Frr-reload needs to move neighbor remote-as line to end and allow
all other config lines to be removed.

Ticket:#3588361 #3589216

Testing Done:
config:
neighbor swp3 interface remote-as external
 neighbor swp3 bfd 3 300 300
 neighbor swp3 password leaf11-spine

INFO: Executed "router bgp 65101  no neighbor swp3 interface remote-as external"
INFO: Failed to execute router bgp 65101  no neighbor swp3 bfd 3 300 300
INFO: Failed to execute router bgp 65101  no neighbor swp3 bfd 3 300
INFO: Failed to execute router bgp 65101  no neighbor swp3 bfd 3
INFO: Failed to execute router bgp 65101  no neighbor swp3 bfd
INFO: Failed to execute router bgp 65101  no neighbor swp3
INFO: Failed to execute router bgp 65101  no neighbor
INFO: Failed to execute router bgp 65101  no
  ERROR: "router bgp 65101 --  no" we failed to remove this command
  ERROR: % Specify remote-as or peer-group commands first

INFO: Failed to execute router bgp 65101  no neighbor swp3 password leaf11-spine
INFO: Failed to execute router bgp 65101  no neighbor swp3 password
INFO: Failed to execute router bgp 65101  no neighbor swp3
INFO: Failed to execute router bgp 65101  no neighbor
INFO: Failed to execute router bgp 65101  no
 ERROR: "router bgp 65101 --  no" we failed to remove this command
 ERROR: % Specify remote-as or peer-group commands first

After fix:

move the neighbor remote-as deletion line to end which allows to remove
other neighbor associated lines to be deleted.
router bgp 65101  no neighbor swp3 interface remote-as external

Signed-off-by: Chirag Shah <chirag@nvidia.com>