WIP: Move LegacyGeoShapeWithDocValuesQueryTests to N-2 compatibility tests

[cbuescher]

This change moves LegacyGeoShapeWithDocValuesQueryTests to the new
N-2 index version compatibility QA project so we can leverage the test infrastructure
to create indices in v7 and test them after the cluster is upgraded to v8 and v9.

The test in question is currently disabled because v7 indices are not supported in v9.
With this change the two most important test cases are moved to the new full cluster
restart framework, restoring the v7 indices via searchable snapshots in v9. When we also
support reading directly from v7 indices, this can be added easily into this test infrastructure.

Currently this PR is still marked WIP because I only moved to test cases over, but the test inherits many more (~30) via GeoShapeQueryTestCase, so adding all of these would require some additional work.
Maybe we can cherry-pick the most important ones here.

[javanna]

I looked a bit at whether these can be replaced with unit tests. I think it's possible, and doing so would simplify tests as well as not require full blown IT tests.

The problem I see is that it is not entirely clear what bit of the compatibility these tests are testing - where are the conditional checks that need to be covered with each test?

In general though, I'd expect them all to be in the mappings code. It is possible to build a mapper service providing a specific index version, see MapperServiceTestCase#createMapperService(IndexVersion version, XContentBuilder mapping) for an example. From there MapperService.documentParser().parseDocument should allow to simulate parsing of the document, which I expect to be the area where the compatibility is, without requiring to index the doc entirely. I wonder if the search is needed as well, if it is, we could still retrieve the mapped field type and simulate querying, but we first need to answer the first question about what these tests are actually testing.