feat: add pyodide_315 support (#2958)

* Add pyodide_315 support

Guarded by cpython_prerelease for the moment.

* Update

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Update constraints to pyodide-build 0.39.0

* Update to 315.0.0a2

* Remove example versions

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

test/utils.py

@@ -281,6 +281,8 @@ def _expected_wheels(
         python_abi_tags = ["cp313-cp313", "cp314-cp314"]
         if EnableGroup.PyodideEoL in enable_groups:
             python_abi_tags.insert(0, "cp312-cp312")
+        if EnableGroup.CPythonPrerelease in enable_groups:
+            python_abi_tags.append("cp315-cp315")
     elif (platform == "android" and python_abi_tags is None) or (
         platform == "ios" and python_abi_tags is None
     ):
@@ -410,6 +412,7 @@ def _expected_wheels(
                 "cp312-cp312": ["pyodide_2024_0_wasm32"],
                 "cp313-cp313": ["pyemscripten_2025_0_wasm32"],
                 "cp314-cp314": ["pyemscripten_2026_0_wasm32"],
+                "cp315-cp315": ["pyemscripten_2026_5_wasm32"],
             }.get(python_abi_tag, [])
 
             if not platform_tags: