GitHub Action: enable the vcpkg binary cache

.github/workflows/develop.yml

@@ -2,15 +2,22 @@ name: CI
 
 on: [push, pull_request, workflow_dispatch]
 
+env: 
+  VCPKG_BINARY_SOURCES: "clear;x-gha,readwrite"
+
 jobs:
   ci-ubuntu:
     name: Build on Linux (Ubuntu)
     runs-on: ubuntu-latest
     steps:
+      - name: Export GitHub Actions cache environment variables
+        uses: actions/github-script@v7
+        with:
+          script: |
+            core.exportVariable('ACTIONS_CACHE_URL', process.env.ACTIONS_CACHE_URL || '');
+            core.exportVariable('ACTIONS_RUNTIME_TOKEN', process.env.ACTIONS_RUNTIME_TOKEN || '');
       - uses: actions/checkout@v4
       - uses: lukka/get-cmake@latest
-      - name: install SDL2
-        run: sudo apt update -y && sudo apt install -y libsdl2-dev
       - name: install dependencies
         run: ./vcpkg.sh
       - name: build
@@ -22,6 +29,12 @@ jobs:
     name: Build on MacOS
     runs-on: macOS-latest
     steps:
+      - name: Export GitHub Actions cache environment variables
+        uses: actions/github-script@v7
+        with:
+          script: |
+            core.exportVariable('ACTIONS_CACHE_URL', process.env.ACTIONS_CACHE_URL || '');
+            core.exportVariable('ACTIONS_RUNTIME_TOKEN', process.env.ACTIONS_RUNTIME_TOKEN || '');
       - uses: actions/checkout@v4
       - uses: lukka/get-cmake@latest
       - name: install dependencies
@@ -30,6 +43,7 @@ jobs:
         run: make build
       - name: build
         run: make test
+
   fmt:
     name: Formatting Check
     runs-on: ubuntu-latest