[SPARK-54471][INFRA] Remove build_python_3.11_macos.yml CI

### What changes were proposed in this pull request?

This PR aims to remove `build_python_3.11_macos.yml` (MacOS 15) CI in favor of `build_python_3.11_macos26.yml` (MacOS 25).

### Why are the changes needed?

Since we successfully migrated to `MacOS25` from `MacOS15`, we can remove the old OS to meet SPARK-48094 (Reduce GitHub Action usage according to ASF project allowance).
- https://github.com/apache/spark/actions/workflows/build_python_3.11_macos26.yml

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Manual review because this is a removal of CI.

### Was this patch authored or co-authored using generative AI tooling?

No.

Closes #53184 from dongjoon-hyun/SPARK-54471.

Authored-by: Dongjoon Hyun <[email protected]>
Signed-off-by: Dongjoon Hyun <[email protected]>
(cherry picked from commit 021f89a)
Signed-off-by: Dongjoon Hyun <[email protected]>

Author: dongjoon-hyun

.github/workflows/build_python_3.11_macos.yml

@@ -39,7 +39,6 @@ This README file only contains basic setup instructions.
 |            | [![GitHub Actions Build](https://github.com/apache/spark/actions/workflows/build_python_3.10.yml/badge.svg)](https://github.com/apache/spark/actions/workflows/build_python_3.10.yml)                           |
 |            | [![GitHub Actions Build](https://github.com/apache/spark/actions/workflows/build_python_3.11_classic_only.yml/badge.svg)](https://github.com/apache/spark/actions/workflows/build_python_3.11_classic_only.yml) |
 |            | [![GitHub Actions Build](https://github.com/apache/spark/actions/workflows/build_python_3.11_arm.yml/badge.svg)](https://github.com/apache/spark/actions/workflows/build_python_3.11_arm.yml)                   |
-|            | [![GitHub Actions Build](https://github.com/apache/spark/actions/workflows/build_python_3.11_macos.yml/badge.svg)](https://github.com/apache/spark/actions/workflows/build_python_3.11_macos.yml)               |
 |            | [![GitHub Actions Build](https://github.com/apache/spark/actions/workflows/build_python_3.11_macos26.yml/badge.svg)](https://github.com/apache/spark/actions/workflows/build_python_3.11_macos26.yml)           |
 |            | [![GitHub Actions Build](https://github.com/apache/spark/actions/workflows/build_python_numpy_2.1.3.yml/badge.svg)](https://github.com/apache/spark/actions/workflows/build_python_numpy_2.1.3.yml)             |
 |            | [![GitHub Actions Build](https://github.com/apache/spark/actions/workflows/build_python_3.12.yml/badge.svg)](https://github.com/apache/spark/actions/workflows/build_python_3.12.yml)                           |