fix: use manual git checkout and conditional package managers for Gitea compatibility

.gitea/workflows/syntax-check.yml

@@ -14,14 +14,21 @@ on:
 
 jobs:
   syntax-check:
-    runs-on: ubuntu-latest
+    runs-on: linux,x86_64,docker
     
     steps:
       - name: Checkout code
-        uses: actions/checkout@v3
+        run: |
+          git clone --depth 1 "$(echo "${{ gitea.server_url }}" | sed "s|://|://oauth2:${{ gitea.token }}@|")/${{ gitea.repository }}.git" .
+          git checkout -q ${{ github.sha }}
       
       - name: Install ShellCheck
-        run: apt-get update && apt-get install -y shellcheck
+        run: |
+          if command -v apk >/dev/null 2>&1; then
+            apk add --no-cache shellcheck
+          elif command -v apt-get >/dev/null 2>&1; then
+            apt-get update && apt-get install -y shellcheck
+          fi
       
       - name: Check bash script syntax
         run: |
@@ -30,7 +37,12 @@ jobs:
           shellcheck example-trigger/deploy.sh
       
       - name: Install PHP
-        run: apt-get install -y php-cli
+        run: |
+          if command -v apk >/dev/null 2>&1; then
+            apk add --no-cache php
+          elif command -v apt-get >/dev/null 2>&1; then
+            apt-get install -y php-cli
+          fi
       
       - name: Check PHP syntax
         run: |