Use raspberrypi/pico-sdk#2315 and raspberrypi/pico-examples#619 so the examples compilation passes

Author: will-v-pi

.github/workflows/test.yml

@@ -82,8 +82,8 @@ jobs:
       - name: Checkout Pico SDK
         uses: actions/checkout@v4
         with:
-          repository: raspberrypi/pico-sdk
-          ref: develop
+          repository: will-v-pi/pico-sdk
+          ref: self-decrypting-only
           path: pico-sdk
           submodules: 'recursive'
       - name: Build and Install
@@ -95,7 +95,7 @@ jobs:
         uses: actions/checkout@v4
         with:
           repository: raspberrypi/pico-examples
-          ref: develop
+          ref: encrypted-improvements
           path: pico-examples
       - name: Build Pico Examples
         run: |