Update pyproject to new briefcase format, and drop Py3.8 support.

Author: freakboy3742

.github/workflows/ci.yml

@@ -45,7 +45,7 @@ jobs:
           - "windows-app"
           - "iOS"
           - "android"
-        python-version: [ "3.8", "3.9", "3.10", "3.11", "3.12", "3.13-dev" ]
+        python-version: [ "3.9", "3.10", "3.11", "3.12", "3.13-dev" ]
         include:
           - runs-on: ubuntu-latest
           - pre-command:
@@ -109,6 +109,8 @@ jobs:
           # Binary packages aren't available for 3.12+ on Android yet
           - backend: android
             python-version: "3.12"
+          - backend: android
+            python-version: "3.13-dev"
 
     steps:
     - name: Checkout

pyproject.toml

@@ -3,7 +3,7 @@ project_name = "Testbed"
 bundle = "org.beeware"
 version = "0.0.1"
 url = "https://beeware.org"
-license = "BSD license"
+license.file = "LICENSE"
 author = 'Russell Keith-Magee'
 author_email = "russell@beeware.org"
 
@@ -36,10 +36,11 @@ requires = [
     "rubicon-objc",
     "std-nslog",
 ]
-# support_package = "../Python-Apple-support/dist/Python-3.8-macOS-support.custom.tar.gz"
+# support_package = "../Python-Apple-support/dist/Python-3.13-macOS-support.custom.tar.gz"
 
 [tool.briefcase.app.testbed.macOS.app]
 # template = "../../templates/briefcase-macOS-app-template"
+# stub_binary = "../../templates/briefcase-macOS-Xcode-template/stub/build/gui-stub/macos/xcode/build/Release/GUI Stub.app/Contents/MacOS/GUI Stub"
 
 [tool.briefcase.app.testbed.macOS.Xcode]
 # template = "../../templates/briefcase-macOS-Xcode-template"
@@ -92,7 +93,7 @@ requires = [
     "rubicon-objc",
     "std-nslog",
 ]
-# support_package = "../Python-Apple-support/dist/Python-3.8-iOS-support.custom.tar.gz"
+# support_package = "../Python-Apple-support/dist/Python-3.13-iOS-support.custom.tar.gz"
 # template = "../../templates/briefcase-iOS-Xcode-template"
 
 [tool.briefcase.app.testbed.android]