### What changes were proposed in this pull request?
Currently, `ResolveAggregateFunctions` is a complicated rule that recursively calls the entire analyzer to resolve aggregate functions in parent nodes of aggregate. It's kind of necessary as we need to do many things to identify the aggregate function and push it down to the aggregate node: resolve columns as if they are in the aggregate node, resolve functions, apply type coercion, etc. However, this is overly complicated and it's hard to fully understand how the resolution is done there. It also leads to hacks such as the [char/varchar hack](https://github.com/apache/spark/blob/v3.1.2/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala#L2396-L2401), [subquery hack](https://github.com/apache/spark/blob/v3.1.2/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala#L2274-L2277), [grouping function hack](https://github.com/apache/spark/blob/v3.1.2/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala#L2465-L2467), etc.
This PR simplifies the `ResolveAggregateFunctions` rule and clarifies the resolution logic. To resolve aggregate functions/grouping columns in HAVING, ORDER BY and `df.where`, we expand the aggregate node below to output these required aggregate functions/grouping columns. In details, when resolving an expression from the parent of an aggregate node:
1. try to resolve columns with `agg.child` and wrap the result with `TempResolvedColumn`.
2. try to resolve subqueries with `agg.child`
3. if the expression is not resolved, return it and wait for other rules to resolve it, such as resolve functions, type coercions, etc.
4. if the expression is resolved, we transform it and push aggregate functions/grouping columns into the aggregate node below.
4.1 the expression may already present in `agg.aggregateExpressions`, we can simply replace the expression with attr ref.
4.2 if a `TempResolvedColumn` is neither inside an aggregate function, or wrap a grouping column, turn it back to an `UnresolvedAttribute`
5. after the main resolution batch, remove all `TempResolvedColumn` and turn them back to `UnresolvedAttribute`.
### Why are the changes needed?
Code cleanup
### Does this PR introduce _any_ user-facing change?
No
### How was this patch tested?
existing test
Closes#32470 from cloud-fan/agg2.
Authored-by: Wenchen Fan <wenchen@databricks.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
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