test(functions): fix iptables normalization for opt field

The sed expression didn't consume multiple spaces. All of the
normalization nuances are stacking. :(

@@ -3,5 +3,5 @@
 IN_public_deny 0 -- ::/0 ::/0
 IN_public_allow 0 -- ::/0 ::/0
 IN_public_post 0 -- ::/0 ::/0
-ACCEPT 58 -- ::/0 ::/0
+ACCEPT 58 -- -- ::/0 ::/0

Fixes: 9a11ab1 ("test(functions): ip6tables: normalize opt field output")
(cherry picked from commit e3f44a7)

src/tests/functions.at

@@ -417,7 +417,7 @@ m4_define([IPXTABLES_LIST_RULES_NORMALIZE], [dnl
     dnl commit 6e41c2d8747b ("iptables: xshared: Output '--' in the opt field
     dnl in ipv6's fake mode") added "--" to the output of ip6tables. This regex
     dnl adds the "--" for older ip6tables versions.
-        -e ['s/^\([-a-zA-Z0-9_]\+\)[ ]\([^ ]*\)[ ][-]\?[-]\?[ ]\?/\1 \2 -- /g'] dnl
+        -e ['s/^\([-a-zA-Z0-9_]\+\)[ ]\+\([^ ]*\)[ ]\+[-]\?[-]\?[ ]\?/\1 \2 -- /g'] dnl
 ])
 
 m4_define([IPTABLES_LIST_RULES_NORMALIZE], [dnl