SDL_image: Enable libwebp in CMake CI builds

SDL Commits
1 
From 0eca53311d4c826c84e7ea34d62f3499fb312ed1 Mon Sep 17 00:00:00 2001
From: Cameron Cawley <[EMAIL REDACTED]>
Date: Mon, 9 May 2022 00:52:16 +0100
Subject: [PATCH] Enable libwebp in CMake CI builds

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

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 288e583..c8c64fa 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -73,6 +73,7 @@ jobs:
           -DBUILD_SHOWIMAGE=ON \
           -DCMAKE_POSITION_INDEPENDENT_CODE=ON \
           -DCMAKE_VERBOSE_MAKEFILE=ON \
+          -DSUPPORT_WEBP=ON \
           ${{ matrix.platform.cmake }}
     - name: Build
       if: "matrix.platform.cmake"