tests/shell: drop unstable dump for "transactions/0051map_0" test

tests/shell: drop unstable dump for "transactions/0051map_0" test

The file "tests/shell/testcases/transactions/dumps/0051map_0.nft" gets
generated differently on Fedora 38 (6.4.14-200.fc38.x86_64) and
CentOS-Stream-9 (5.14.0-354.el9.x86_64). It's not stable.

    diff --git c/tests/shell/testcases/transactions/dumps/0051map_0.nft w/tests/shell/testcases/transactions/dumps/0051map_0.nft
    index 59d69df70e61..fa7df9f93757 100644
    --- c/tests/shell/testcases/transactions/dumps/0051map_0.nft
    +++ w/tests/shell/testcases/transactions/dumps/0051map_0.nft
    @@ -1,7 +1,11 @@
     table ip x {
    +    chain w {
    +    }
    +
         chain m {
         }

         chain y {
    +         ip saddr vmap { 1.1.1.1 : jump w, 2.2.2.2 : accept, 3.3.3.3 : goto m }
         }
     }

Drop it.

Signed-off-by: Thomas Haller <thaller@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>