Update Formula/s/sdl3_mixer.rb

Co-authored-by: Carlo Cabrera <github@carlo.cab>

Author: atticus5

Formula/s/sdl3_mixer.rb

@@ -25,8 +25,8 @@ class Sdl3Mixer < Formula
   depends_on "wavpack"
 
   def install
-    system "cmake", "-S", ".",
-                    "-B", "build",
+    system "cmake", "-S", ".", "-B", "build",
+                    "-DBUILD_SHARED_LIBS=ON",
                     "-DSDLMIXER_DEPS_SHARED=OFF",
                     "-DSDLMIXER_VENDORED=OFF",
                     *std_cmake_args