github ci: change to Xcode 13 beta

Signed-off-by: Finn Behrens <[email protected]>

Author: kloenk

.github/workflows/ci-build.yml

@@ -16,7 +16,7 @@ env:
 jobs:
   build:
     name: Build
-    runs-on: macos-latest
+    runs-on: macos-11
 
     steps:
       - uses: actions/checkout@v2

.github/workflows/ci-tests.yml

@@ -16,7 +16,7 @@ env:
 jobs:
   tests:
     name: Tests
-    runs-on: macos-latest
+    runs-on: macos-11
 
     steps:
       - uses: actions/checkout@v2

.github/workflows/release-alpha.yml

@@ -15,7 +15,7 @@ env:
 jobs:
   build:
     name: Release
-    runs-on: macos-latest
+    runs-on: macos-11
 
     steps:
       - uses: actions/checkout@v2

fastlane/Fastfile

@@ -21,7 +21,7 @@ platform :ios do
 
   before_all do
     # Ensure used Xcode version
-    xcversion(version: "~> 12.1")
+    xcversion(version: "~> 13.0")
   end
 
   #### Public ####