Test 3.15t on Ubuntu, 3.15+3.15t on Windows/macOS (#175)

Author: hugovk

.github/workflows/build.yml

@@ -1,10 +1,6 @@
 name: Build
 
-on:
-  push:
-    branches: [main]
-  pull_request:
-    branches: [main]
+on: [push, pull_request, workflow_dispatch]
 
 jobs:
   build:
@@ -33,9 +29,8 @@ jobs:
           - "3.13t"
           - "3.14"
           - "3.14t"
-          # CPython 3.15 final is scheduled for October 2026:
-          # https://peps.python.org/pep-0790/
-          - "3.15-dev"
+          - "3.15"
+          - "3.15t"
 
           # PyPy versions:
           # - https://github.com/actions/setup-python/blob/main/docs/advanced-usage.md
@@ -78,6 +73,10 @@ jobs:
             python: "3.14"
           - os: windows-latest
             python: "3.14t"
+          - os: windows-latest
+            python: "3.15"
+          - os: windows-latest
+            python: "3.15t"
 
           # macOS
           # Python 3.9 is the oldest version available on macOS/arm64.
@@ -97,6 +96,10 @@ jobs:
             python: "3.14"
           - os: macos-latest
             python: "3.14t"
+          - os: macos-latest
+            python: "3.15"
+          - os: macos-latest
+            python: "3.15t"
 
           # Ubuntu: test deadsnakes Python versions which are not supported by
           # GHA python-versions.