### Godot version

4.0.beta14

### System information

windows 10, gles 3, nvidia graphics

### Issue description

SCREEN_TEXTURE  was dropped in beta 14. The suggested replacement is to use ```uniform sampler2D SCREEN_TEXTURE : hint_screen_texture, filter_linear_mipmaps;```, but filter_linear_mipmaps is not recognized as a valid shader type hint and a shader using it fails to compile.

### Steps to reproduce

Create a canvas item shader and use the filter_linear_mipmaps type hint with a sampler2D uniform.

### Minimal reproduction project

N/A
st.shader_struct = st_node;
				int member_count = 0;
				HashSet<String> member_names;
				while (true) { 
#ifdef DEBUG_ENABLED
					keyword_completion_context = CF_DATATYPE | CF_PRECISION_MODIFIER;
#endif 
					tk = _get_token();
					if (tk.type == TK_CURLY_BRACKET_CLOSE) {
						break;
					}
					StringName struct_name = "";
					bool struct_dt = false;
					DataPrecision precision = PRECISION_DEFAULT;
					if (tk.type == TK_STRUCT) {
						_set_error(RTR("Nested structs are not allowed."));
						return ERR_PARSE_ERROR;
					}
					if (is_token_precision(tk.type)) {
						precision = get_token_precision(tk.type);
						tk = _get_token();
#ifdef DEBUG_ENABLED
						keyword_completion_context ^= CF_PRECISION_MODIFIER;
#endif 
					}
					if (shader->structs.has(tk.text)) {
						struct_name = tk.text;
#ifdef DEBUG_ENABLED
						if (check_warnings && HAS_WARNING(ShaderWarning::UNUSED_STRUCT_FLAG) && used_structs.has(struct_name)) {
							used_structs[struct_name].used = true;