fix mpool leak in txn.WriteBatch

[ouyuanning]

What type of PR is this?

• API-change
• BUG
• Improvement
• Documentation
• Feature
• Test and CI
• Code Refactoring

Which issue(s) this PR fixes:

issue #14080

What this PR does / why we need it:

fix mpool leak in txn.WriteBatch

[matrix-meow]

@ouyuanning Thanks for your contributions!

Review:

Title: fix mpool leak in txn.WriteBatch

Body: This pull request fixes a memory pool (mpool) leak in the txn.WriteBatch function.

Changes:

1. In engine.go, the Clean method is called on the bat object using txn.proc.Mp() instead of e.mp in the Create and Delete functions.
2. In txn_database.go, the Clean method is called on the bat object using db.txn.proc.Mp() instead of db.txn.engine.mp in the Delete, Truncate, Create, and AlterTable functions.
3. In txn_table.go, the Clean method is called on the bat object using tbl.db.txn.proc.Mp() instead of tbl.db.txn.engine.mp in the UpdateConstraint, AlterTable, Write, and writeTnPartition functions.
4. In types.go, the Clean method is called on the bat object using txn.proc.Mp() instead of txn.engine.mp in the RollbackLastStatement function.

Problem 1: Memory Pool Leak
In the engine.go file, the bat.Clean method is called using txn.proc.Mp() instead of e.mp in the Create and Delete functions. This can lead to a memory pool leak if the bat object is not properly cleaned up.

Solution 1: Use the Correct Memory Pool
To fix this issue, the bat.Clean method should be called using e.mp instead of txn.proc.Mp() in the Create and Delete functions.

Problem 2: Memory Pool Leak
In the txn_database.go file, the bat.Clean method is called using db.txn.proc.Mp() instead of db.txn.engine.mp in the Delete, Truncate, Create, and AlterTable functions. This can lead to a memory pool leak if the bat object is not properly cleaned up.

Solution 2: Use the Correct Memory Pool
To fix this issue, the bat.Clean method should be called using db.txn.engine.mp instead of db.txn.proc.Mp() in the Delete, Truncate, Create, and AlterTable functions.

Problem 3: Memory Pool Leak
In the txn_table.go file, the bat.Clean method is called using tbl.db.txn.proc.Mp() instead of tbl.db.txn.engine.mp in the UpdateConstraint, AlterTable, Write, and writeTnPartition functions. This can lead to a memory pool leak if the bat object is not properly cleaned up.

Solution 3: Use the Correct Memory Pool
To fix this issue, the bat.Clean method should be called using tbl.db.txn.engine.mp instead of tbl.db.txn.proc.Mp() in the UpdateConstraint, AlterTable, Write, and writeTnPartition functions.

Problem 4: Memory Pool Leak
In the types.go file, the bat.Clean method is called using txn.proc.Mp() instead of txn.engine.mp in the RollbackLastStatement function. This can lead to a memory pool leak if the bat object is not properly cleaned up.

Solution 4: Use the Correct Memory Pool
To fix this issue, the bat.Clean method should be called using txn.engine.mp instead of txn.proc.Mp() in the RollbackLastStatement function.

Optimization Suggestions:

• It would be helpful to add comments explaining the purpose of the changes made in each function.
• Consider using more descriptive variable names to improve code readability.
• It may be beneficial to refactor the code to reduce code duplication and improve maintainability.

Overall, this pull request addresses a memory pool leak issue in the txn.WriteBatch function. The suggested changes involve using the correct memory pool and adding comments for clarity. Additionally, optimizing the code by refactoring and using descriptive variable names can improve the quality and readability of the codebase.