Add existing to tracked

node_modules/@cesium/engine/Source/Shaders/SkyBoxFS.js

@@ -0,0 +1,11 @@
+//This file is automatically rebuilt by the Cesium build process.
+export default "uniform samplerCube u_cubeMap;\n\
+\n\
+in vec3 v_texCoord;\n\
+\n\
+void main()\n\
+{\n\
+    vec4 color = czm_textureCube(u_cubeMap, normalize(v_texCoord));\n\
+    out_FragColor = vec4(czm_gammaCorrect(color).rgb, czm_morphTime);\n\
+}\n\
+";