fix(test): increase timeout on waiting for xds messages to propagate

[lobkovilya]

Apparently, 60s timeout is not enough. Test constantly fails, the last 3 runs:

• https://github.com/Kong/mesh-perf/actions/runs/6006322432/job/16290654415
• https://github.com/Kong/mesh-perf/actions/runs/5994016318/job/16255096719
• https://github.com/Kong/mesh-perf/actions/runs/5970239579/job/16197508252