Fixed vertex color initialization with default value in gles3

Fixes #30275, #31250

(cherry picked from commit e852b3a2712e0d67c71b220a27bac09b25d2c35f)

drivers/gles3/rasterizer_canvas_gles3.cpp

@@ -200,6 +200,8 @@ void RasterizerCanvasGLES3::canvas_end() {
 	glBindBufferBase(GL_UNIFORM_BUFFER, 0, 0);
 	glColorMask(1, 1, 1, 1);
 
+	glVertexAttrib4f(VS::ARRAY_COLOR, 1, 1, 1, 1);
+
 	state.using_texture_rect = false;
 	state.using_ninepatch = false;
 }