All iPhones before iPhone X and iPhones with a physical home button do not have a tap to wake feature and will not come in the software update due to the display the iPhone has. This is because tap to wake drains a lot of battery on an LCD; this is because when tap to wake is enabled (on iPhone x & above or iPhones that don't have a physical home button), the iPhone screen goes into a sort of low power mode because it needs to have constant power to recognize when you touch the display and since OLED display doesn't require much power and therefore it's able to have the touch to wake feature and phones that don't have a physical home button can have the feature as well.
I would strongly recommend that you do not jailbreak your iPhone, and it's best to live without the tap to wake or upgrade to an iPhone x and above or an iPhone that doesn't have a physical home button if you want the tap to wake feature.
With the shortcuts app, you have no control over something like this. Even if you did, then it would be a problem because it all comes back to the display and the use of power and also the fact even if Apple allowed this, then they could have just introduced the tap to wake in an update anyway but can't because of the LCD on the iPhone.
If you jailbreak to get this tap to wake, then you will be putting your iPhone at risk because you are essentially removing the security that Apple has put in place to protect your device from being hacked in the first place. Despite what people say about iPhone cannot get viruses and cannot be hacked; this true if you don't jailbreak your iPhone and note this, viruses and exploits are built to target iPhones and they are out there. Still, Apple is great at deflecting them, but if a hacker finds that you have a jailbroken iPhone, then I wish you the best of luck.
So either upgrade to an iPhone that has the tap to wake or just live without it and don't jailbreak your iPhone.