### Godot version

8449592d92eaeef990f5502b419d491ee3eeb7a6

### System information

Windows 11

### Issue description

Zooming in the script editor on an empty script freezes the entire editor for a few seconds, but if the file is large then it freezes for 4-5 seconds (which is unacceptable). Looks like a recent regression.

### Steps to reproduce

Just zoom in/out on the large script file.

### Minimal reproduction project

N/A
FontAdvanced *fd = font_owner.get_or_null(p_font_rid);
	ERR_FAIL_COND_V(!fd, Vector2());
	MutexLock lock(fd->mutex);
	Vector2i size = _get_size(fd, p_size);
	ERR_FAIL_COND_V(!_ensure_cache_for_size(fd, size), Vector2());
	const HashMap<Vector2i, Vector2> &kern = fd->cache[size]->kerning_map;
	if (kern.has(p_glyph_pair)) {
		if (fd->msdf) {
			return kern[p_glyph_pair] * (double)p_size / (double)fd->msdf_source_size;
		} else {
			return kern[p_glyph_pair];
		}
	} else {
#ifdef MODULE_FREETYPE_ENABLED
		if (fd->cache[size]->face) {
			FT_Vector delta;
			FT_Get_Kerning(fd->cache[size]->face, p_glyph_pair.x, p_glyph_pair.y, FT_KERNING_DEFAULT, &delta);
			if (fd->msdf) {
				return Vector2(delta.x, delta.y) * (double)p_size / (double)fd->msdf_source_size;
			} else {
				return Vector2(delta.x, delta.y);
			}
		}
#endif
	}
	return Vector2();
}
int64_t TextServerAdvanced::_font_get_glyph_index(const RID &p_font_rid, int64_t p_size, int64_t p_char, int64_t p_variation_selector) const {