fix(ci): assert the base wheel's real console script name (release-1.11.4) (#14572)

fix(ci): assert the base wheel's real console script name

The "Base Distribution Wheel" job verified that the base-only environment
exposes a `langflow` console script and no `langflow-base` one. That is
inverted: `langflow-base` declares `langflow-base = langflow.langflow_launcher:main`,
while the `langflow` script belongs to the root `langflow` distribution --
which the same step explicitly forbids from that environment. The assertion
could never pass, and the follow-on boot step invoked `bin/langflow`, which
does not exist there either.

These expectations were carried over from the langflow-core wheel this job
used to test (#14352) and were never re-pointed at langflow-base. Swap both
script assertions, give them failure messages so a future break is not a bare
AssertionError, and boot the server via `bin/langflow-base`, matching
`docker/build_and_push_base.Dockerfile`.