selftests: tc-testing: test action batch failure cleanup

Add tests for cleanup after a batched RTM_NEWACTION request fails.
Replace an existing gact action bound to a filter, then fail a later
entry by requesting goto chain without a classifier context.

Check that the bound action's reference count returns to its original
value. Also cover a successfully initialized new action between the
bound action and the failing entry, verifying that its reserved index
can be reused. Repeat the bound action in another batch to check that
each temporary reference to the same action is released.

Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260909070336.32979-3-xuanqiang.luo@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>