Fix elastic#129372

Due to how remote ENRICH is
[planned](https://github.com/elastic/elasticsearch/blob/32e50d0d94e27ee559d24bf9d5463ba6e64d1788/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/planner/mapper/Mapper.java#L93),
it interacts in special ways with pipeline breakers, in particular LIMIT
and TopN; when these are encountered upstream from a remote ENRICH,
these nodes are copied and executed a second time after the remote
ENRICH.

We'd like to allow remote ENRICH after LOOKUP JOIN, but that forces the
lookup to be remote as well; this has its own interactions with pipeline
breakers: in particular, LIMITs and TopNs cannot just be duplicated
after LOOKUP JOIN, as LOOKUP JOIN may add new rows.

For now, let's just forbid any usage of remote ENRICH after LOOKUP
JOINs; remote ENRICH is mostly relevant for CCS, and LOOKUP JOIN doesn't
support that in 9.1/8.19, anyway.

There is separate work that enables remote LOOKUP JOINs on remote
clusters and adds the correct validations; we can later build support
for remote ENRICH + LOOKUP JOIN on top of that. (C.f. my comment
[here](elastic#129372 (comment))
and my draft elastic#131286 for
enabling this.)

(cherry picked from commit 06e39c0)

# Conflicts:
#	x-pack/plugin/esql/qa/server/multi-clusters/src/javaRestTest/java/org/elasticsearch/xpack/esql/ccq/MultiClusterSpecIT.java
#	x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/VerifierTests.java