Remove static prune mode for partition table

[Defined2014]

Feature Request

(Planned to achieve after the v9.1 branch is created)

Is your feature request related to a problem? Please describe:

• The static prune mode encountered many issues previously, and its presence offered no benefits, so we can consider removing it. The issue lists shown below, but not limited to this:
  • panic during partition location for key and hash partition #54667
  • return wrong results when accessing partition tables with tablesample #52282
  • Inconsistent query result after changing the order of cte statements #51873
  • UnionExec reports error with static pruning #45757
  • static pruning mode gets wrong results #35295
• And also static prune mode has many related codes and test cases in TiDB repo. After removing those codes, it could make repo cleaner.
• dynamic prune mode already became the default mode since v6.5, which I think is enough to prove its stability.

Describe the feature you'd like:

• Remove static prune related codes.
• Deprecated tidb_partition_prune_mode session variable and always set it to dynamic.

Describe alternatives you've considered:

None

Teachability, Documentation, Adoption, Migration Strategy:

Need remove static prune related docs, I haven't thought of anything else yet.

Because there are many related codes, maybe we could split this issue to some PRs, including but not limited to the ones listed below

• sessionctx: Deprecate static prune mode #56543
• Let tidb_partition_prune_mode always set to dynamic
• Deprecate and remove table partition in optimize hint #33002
• Remove related codes in analyze pkg

Some issues can close after this PR finish:

• planner: PartitionUnion is not supported by tidb_decode_plan #27241
• INL_JOIN hint is not used correctly #23582
• hashAgg panic when UpdatePartialResult  #40470
• for all test with tidb_partition_prune_mode static, also run them with dynamic prune mode #33000
• Inconsistent result after disabling partition_processor #58025
• TiDB 4.0.x use '500 partitions table' "slow query log" generate large files #22063