sdl12-compat: CI: added some debug info

From 881d69ea965b7b9be6632f7d8fbee533c9121a76 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Tue, 1 Jun 2021 18:23:38 -0400
Subject: [PATCH] CI: added some debug info

---
 .github/workflows/main.yml | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 77b9223..3ed79b9 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -24,6 +24,12 @@ jobs:
         repository: libsdl-org/SDL
         ref: release-2.0.14
         path: SDL2
+    - name: Sanity check SDL2 headers 1
+      run: ls -l "${{ github.workspace }}"
+    - name: Sanity check SDL2 headers 2
+      run: ls -l "${{ github.workspace }}/SDL2"
+    - name: Sanity check SDL2 headers 3
+      run: ls -l "${{ github.workspace }}/SDL2/include"
     - name: Get sdl12-compat sources
       uses: actions/checkout@v2
     - name: Configure CMake