[CI][Integration] conda-integration fails to install jpype1 with Python 3.15 #54489

Describe the bug, including details regarding any error messages, version, and platform.

Building the conda-integration image from scratch now gives Python 3.15.0. The integration run then fails in ci/scripts/integration_arrow.sh at pip install jpype1. jpype1 1.7.1 has no cp315 wheel on PyPI (its newest wheels are cp314), so pip builds it from source, and the build needs Apache Ant, which the image doesn't include:

+ pip install jpype1
Collecting jpype1
  Downloading jpype1-1.7.1.tar.gz (783 kB)
...
      CMake Error at CMakeLists.txt:43 (find_program):
        Could not find ANT_EXECUTABLE using the following names: ant
...
ERROR: Failed building wheel for jpype1

Python is no longer pinned in this image (#51099), so it follows conda-forge's default, which moved from 3.14 to 3.15 within the last week. This breaks the Integration job in apache/arrow-dotnet, which builds this image from apache/arrow main. That job has failed on every run since Oct 18; the last successful run, on Oct 12, used Python 3.14 and a prebuilt jpype1-1.7.1-cp314 wheel. Example failure: https://github.com/apache/arrow-dotnet/actions/runs/39147945839/job/117735520032

The integration runs in this repository still pass, presumably because they reuse cached images built before the switch, so they'll likely hit the same failure the next time the image is rebuilt.

conda-forge already publishes jpype1 1.7.1 for Python 3.15 on linux-64 and linux-aarch64. Installing jpype1 with mamba in conda-integration.dockerfile, as conda-python-jpype.dockerfile already does, would avoid the source build.

Component(s)

Continuous Integration, Integration