Fix GitHub API call for fetching PR preview folders

Co-authored-by: leofang <[email protected]>

Author: Copilot

ci/cleanup-pr-previews

@@ -104,10 +104,28 @@ echo -e "${GREEN}[INFO]${NC} All prerequisites satisfied"
 echo -e "${YELLOW}[INFO]${NC} Fetching PR preview folders from gh-pages branch..."
 
 # Get the list of pr-XXXXX folders from gh-pages branch
-PR_FOLDERS=$(gh api repos/"${REPOSITORY}"/contents/docs/pr-preview \
-    --header "Accept: application/vnd.github+json" \
-    --jq '.[] | select(.type == "dir" and (.name | test("^pr-[0-9]+$"))) | .name' \
-    --field ref=gh-pages 2>/dev/null || true)
+echo -e "${YELLOW}[INFO]${NC} Fetching PR preview folders from gh-pages branch..."
+
+# Try to get the contents of docs/pr-preview directory
+API_RESPONSE=$(gh api repos/"${REPOSITORY}"/contents/docs/pr-preview --field ref=gh-pages 2>/dev/null || echo "ERROR")
+
+if [[ "$API_RESPONSE" == "ERROR" ]] || echo "$API_RESPONSE" | jq -e '.message' >/dev/null 2>&1; then
+    # API call failed or returned an error message
+    if echo "$API_RESPONSE" | jq -e '.message' >/dev/null 2>&1; then
+        ERROR_MSG=$(echo "$API_RESPONSE" | jq -r '.message')
+        echo -e "${RED}[ERROR]${NC} GitHub API error: ${ERROR_MSG}" >&2
+    else
+        echo -e "${RED}[ERROR]${NC} Failed to fetch PR preview folders from gh-pages branch" >&2
+    fi
+    echo -e "${YELLOW}[INFO]${NC} This could be because:" >&2
+    echo -e "  - The gh-pages branch doesn't exist" >&2
+    echo -e "  - The docs/pr-preview directory doesn't exist in gh-pages" >&2
+    echo -e "  - Authentication issues with GH_TOKEN" >&2
+    exit 1
+fi
+
+# Parse the response to get folder names
+PR_FOLDERS=$(echo "$API_RESPONSE" | jq -r '.[] | select(.type == "dir" and (.name | test("^pr-[0-9]+$"))) | .name' 2>/dev/null || true)
 
 if [[ -z "$PR_FOLDERS" ]]; then
     echo -e "${YELLOW}[INFO]${NC} No PR preview folders found in gh-pages branch"