[Build] Lift macOS min compat version to Big Sur (#8583)

Author: feisuzhu

.github/workflows/release.yml

@@ -125,8 +125,8 @@ jobs:
     needs: matrix_prep
     strategy:
       fail-fast: false
-      matrix: ${{ fromJson(needs.matrix_prep.outputs.matrix) }}
-    runs-on: [self-hosted, macos-10.15]
+      matrix: ${{ fromJson(needs.matrix_prep.outputs.matrix_osx) }}
+    runs-on: [self-hosted, macos-11]
     env:
       PY: ${{ matrix.python }}
       CXX: clang++

.github/workflows/testing.yml

@@ -119,7 +119,7 @@ jobs:
       matrix:
         include:
           - os: macos-10.15
-            python: 3.7
+            python: 3.11
             with_cpp_tests: ON
             wanted_archs: 'cpu,vulkan'
     runs-on: