Fix add liquidity proportional integration test failing on CI

[brunoguerios]

A single integration test scenario running on gnosis chain was added.
It passes locally, but fails on CI, apparently due to some missing config (more details here)
Currently the test is being skipped so the fix is pushed to prod, but it would be nice to investigate and get it working on CI as well

Ps: adding liquidity proportionally to any boosted pool with their wrapped tokens (instead of underlying ones) should be enough to test this implementation - in other words, using regular router instead of the composite router