…0163)

### What problem does this PR solve?

Issue Number: None

Related PR: #68206, #68636, #68368

Problem Summary:

**In short.** Three branch-4.2 backports of master fixes each added a
test: #68206 (of #61342), #68636 (of #57006) and #68368 (of #66354).
Master has the three fixes but none of the tests. This PR ports them.
Two guard a fix that has no test on master; the third keeps the
ClickBench `query1` shape case from failing whenever the exact row count
of `hits` is cached. The PR changes tests only.

**Background, and what each test covers.**

- *Old primary key metadata (#61342, #68206).* A `PrimaryKeyConstraint`
written before its foreign table collections existed has no `ft`, `ftn`
or `ftni` in its JSON. Gson builds the object without its field
initializers, so these stay null unless `gsonPostProcess` fills them in,
and an FE that replays the journal from the start (without an image, or
with `metadata_failure_recovery`) failed with a NullPointerException.
#61342 added the null checks without a test; #68206 added one on
branch-4.2 for `ft`, the only collection there. The new
`PrimaryKeyConstraintTest` removes all three from a serialized
constraint, loads it, and adds, renames and removes a foreign table on
it.
- *Shadow index columns (#57006, #68636).* During a schema change the
new schema names a changed column `__doris_shadow_<name>`.
`Index.getColumnUniqueIds` compares the index's column names with the
schema's after `Column.removeNamePrefix`, so the new tablet metadata
keeps the index column's unique id. #57006 has no test; #68636 added one
to `IndexTest`, ported here to JUnit 5.
- *ClickBench query1 shape (#66354, #68368).*
`shape_check/clickbench/query1` checks the plan of `SELECT COUNT(*) FROM
hits`. Once `SimpleAggCacheMgr` has cached the exact row count of
`hits`, `REWRITE_SIMPLE_AGG_TO_CONSTANT` turns the count into a constant
and the shape into `PhysicalOneRowRelation`, so the case fails whenever
that cache is warm when it runs. It did on P0 for #69830 (build 1087320:
expected `--hashAgg[GLOBAL]`, real `--PhysicalOneRowRelation`), a PR
that does not touch the planner. On branch-4.2, #68368 disables the rule
in this case together with the cost model change it backports, which
master has from #66354. This PR disables it the same way; the expected
output does not change.

**Results.**

| Change | Test | Result |
|---|---|---|
| none | `PrimaryKeyConstraintTest` (new), `IndexTest` (one new case),
`ConstraintManagerTest`, `ConstraintPersistTest` | pass |
| `gsonPostProcess` without its null checks | `PrimaryKeyConstraintTest`
| fails: NullPointerException while loading |
| `getColumnUniqueIds` without `removeNamePrefix` |
`IndexTest#testGetColumnUniqueIdsForShadowColumn` | fails: `expected
[107] but was []` |
| `query1` as on master, row count of `hits` cached (local cluster) |
`shape_check/clickbench/query1` | fails: `PhysicalOneRowRelation` |
| `query1` with this PR, same cache | `shape_check/clickbench/query1` |
passes |

On the local cluster, `explain shape plan SELECT COUNT(*) FROM hits`
gives `hashAgg[GLOBAL]` the first time and `PhysicalOneRowRelation`
three seconds later, once the asynchronous row count load has finished;
with the rule disabled it stays `hashAgg[GLOBAL]`.

Co-authored-by: minghong <[email protected]>
Co-authored-by: Jack <[email protected]>
Co-authored-by: feiniaofeiafei <[email protected]>