PYTHON-5027 Test Windows with Python 3.14t

Author: blink1073

.evergreen/generated_configs/variants.yml

@@ -319,6 +319,15 @@ buildvariants:
     expansions:
       PYTHON_BINARY: /Library/Frameworks/PythonT.Framework/Versions/3.13/bin/python3t
     tags: []
+  - name: free-threaded-win64-python3.14t
+    tasks:
+      - name: .free-threading
+    display_name: Free-threaded Win64 Python3.14t
+    run_on:
+      - windows-64-vsMulti-small
+    expansions:
+      PYTHON_BINARY: C:/python/Python314t/python.exe
+    tags: []
 
   # Green framework tests
   - name: green-eventlet-rhel8

.evergreen/scripts/generate_config.py

@@ -108,14 +108,14 @@ def create_free_threaded_variants() -> list[BuildVariant]:
     variants = []
     for host_name in ("rhel8", "macos", "macos-arm64", "win64"):
         if host_name == "win64":
-            # TODO: PYTHON-5027
-            continue
+            python = "3.14t"
+        else:
+            python = "3.13t"
         tasks = [".free-threading"]
         tags = []
         if host_name == "rhel8":
             tags.append("pr")
         host = HOSTS[host_name]
-        python = "3.13t"
         display_name = get_variant_name("Free-threaded", host, python=python)
         variant = create_variant(tasks, display_name, tags=tags, python=python, host=host)
         variants.append(variant)