Clean up some old snapshot files.

`tests/out/glsl/operators.main.Fragment.glsl` is no longer generated because the
function in question changed to a Compute entry point.

`tests/out/wgsl/multiple_entry_points-glsl.wgsl` is no longer generated because
the input test was removed in 057dc310.

tests/out/glsl/operators.main.Fragment.glsl

@@ -1,35 +0,0 @@
-#version 310 es
-
-precision highp float;
-
-layout(location = 0) out vec4 _fs2p_location0;
-
-vec4 splat() {
-    vec2 a = (((vec2(1.0) + vec2(2.0)) - vec2(3.0)) / vec2(4.0));
-    ivec4 b = (ivec4(5) % ivec4(2));
-    return (a.xyxy + vec4(b));
-}
-
-int unary() {
-    if ((! true)) {
-        return 1;
-    } else {
-        return (~ 1);
-    }
-}
-
-int unary1() {
-    if ((! true)) {
-        return 1;
-    } else {
-        return (~ 1);
-    }
-}
-
-void main() {
-    vec4 vector1_ = vec4(1.0);
-    vec4 vector2_ = vec4(1.0);
-    _fs2p_location0 = (true ? vector1_ : vector2_);
-    return;
-}
-

tests/out/wgsl/multiple_entry_points-glsl.wgsl

@@ -1,53 +0,0 @@
-struct VertexOutput {
-    [[builtin(position)]] member: vec4<f32>;
-};
-
-struct FragmentOutput {
-    [[location(0)]] o_color: vec4<f32>;
-};
-
-var<private> gl_Position: vec4<f32>;
-var<private> o_color: vec4<f32>;
-var<private> gl_GlobalInvocationID: vec3<u32>;
-
-fn vert_main1() {
-    gl_Position = vec4<f32>(1.0, 1.0, 1.0, 1.0);
-    return;
-}
-
-fn frag_main1() {
-    o_color = vec4<f32>(1.0, 1.0, 1.0, 1.0);
-    return;
-}
-
-fn comp_main1() {
-    let _e3: vec3<u32> = gl_GlobalInvocationID;
-    if ((_e3.x > u32(1))) {
-        {
-            return;
-        }
-    } else {
-        return;
-    }
-}
-
-[[stage(vertex)]]
-fn vert_main() -> VertexOutput {
-    vert_main1();
-    let _e3: vec4<f32> = gl_Position;
-    return VertexOutput(_e3);
-}
-
-[[stage(fragment)]]
-fn frag_main() -> FragmentOutput {
-    frag_main1();
-    let _e3: vec4<f32> = o_color;
-    return FragmentOutput(_e3);
-}
-
-[[stage(compute), workgroup_size(1, 1, 1)]]
-fn comp_main([[builtin(global_invocation_id)]] param: vec3<u32>) {
-    gl_GlobalInvocationID = param;
-    comp_main1();
-    return;
-}