Revert "Add upgrade guide for PhysicalOptimizerRule::optimize_plan (apache#19030)"

This reverts commit 7b4593f.

Author: adriangb

docs/source/library-user-guide/upgrading.md

@@ -380,102 +380,6 @@ If you were using a custom `SchemaAdapterFactory` for schema adaptation (e.g., d
 
 See the [default column values example](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/custom_data_source/default_column_values.rs) for how to implement a custom `PhysicalExprAdapterFactory`.
 
-### `PhysicalOptimizerRule::optimize` deprecated in favor of `optimize_plan`
-
-The `PhysicalOptimizerRule` trait has been updated to provide optimizer rules with access to broader session context. A new method `optimize_plan` has been added that accepts an `OptimizerContext` parameter, and the existing `optimize` method has been deprecated.
-
-**Who is affected:**
-
-- Users who have implemented custom `PhysicalOptimizerRule` implementations
-
-**Breaking changes:**
-
-1. **New `optimize_plan` method**: This is the preferred method for implementing optimization rules. It provides access to the full `SessionConfig` through `OptimizerContext`, rather than just `ConfigOptions`.
-
-2. **`optimize` method deprecated**: The old `optimize` method that takes `&ConfigOptions` is now deprecated and will be removed in DataFusion 58.0.0.
-
-**Migration guide:**
-
-If you have a custom `PhysicalOptimizerRule` implementation, update it to implement `optimize_plan` instead of `optimize`:
-
-**Before:**
-
-```rust
-use datafusion::physical_optimizer::PhysicalOptimizerRule;
-use datafusion_common::config::ConfigOptions;
-use datafusion_common::Result;
-use datafusion_physical_plan::ExecutionPlan;
-use std::sync::Arc;
-
-#[derive(Debug)]
-struct MyOptimizerRule;
-
-#[allow(deprecated)]
-impl PhysicalOptimizerRule for MyOptimizerRule {
-    fn optimize(
-        &self,
-        plan: Arc<dyn ExecutionPlan>,
-        _config: &ConfigOptions,
-    ) -> Result<Arc<dyn ExecutionPlan>> {
-        // Use config.optimizer, config.execution, etc.
-        // ... optimization logic ...
-        Ok(plan)
-    }
-
-    fn name(&self) -> &str {
-        "my_optimizer_rule"
-    }
-
-    fn schema_check(&self) -> bool {
-        true
-    }
-}
-```
-
-**After:**
-
-```rust
-use datafusion::physical_optimizer::{OptimizerContext, PhysicalOptimizerRule};
-use datafusion_common::Result;
-use datafusion_physical_plan::ExecutionPlan;
-use std::sync::Arc;
-
-#[derive(Debug)]
-struct MyOptimizerRule;
-
-impl PhysicalOptimizerRule for MyOptimizerRule {
-    fn optimize_plan(
-        &self,
-        plan: Arc<dyn ExecutionPlan>,
-        context: &OptimizerContext,
-    ) -> Result<Arc<dyn ExecutionPlan>> {
-        // Access ConfigOptions through session_config
-        let _config = context.session_config().options();
-        // Or access extensions through session_config
-        let _extensions = context.session_config().extensions();
-        // ... optimization logic ...
-        Ok(plan)
-    }
-
-    fn name(&self) -> &str {
-        "my_optimizer_rule"
-    }
-
-    fn schema_check(&self) -> bool {
-        true
-    }
-}
-```
-
-**What is `OptimizerContext`?**
-
-`OptimizerContext` is a new struct that provides context during physical plan optimization, similar to how `TaskContext` provides context during execution. It wraps `SessionConfig`, giving optimizer rules access to:
-
-- Configuration options via `context.session_config().options()`
-- Session extensions via `context.session_config().extensions()`
-
-This enables optimizer rules to access custom extensions registered with the session, which was not possible with the old `&ConfigOptions` parameter.
-
 ## DataFusion `51.0.0`
 
 ### `arrow` / `parquet` updated to 57.0.0