Deploy to Heroku no longer possible for free

[AnaFCPreto]

Describe the bug
The Heroku add-on "Temporize Scheduler" no longer has a Free plan.
Upon a little research, I found 7 other schedulers out of which 4 of them have perpetual free plans.

To Reproduce
Steps to reproduce the behavior:

1. Go to the main Github landing page of this repo.
2. Click on the Deploy to Heroku button.
3. Scroll down to Add-ons.
4. Notice there's no longer a free plan for the mentioned add-on.

Expected behavior
Use a free scheduler service.

Screenshots
I don't believe this is required to be honest.

Desktop (please complete the following information):

• OS: Windows 10 Pro x64
• Browser: Chrome
• Version: 90.0

Additional context
N/A

PS: these are the free ones I found: Heroku Scheduler ; Advanced Scheduler ; Process Scheduler ; DeadMan Snitch . Not entirely sure if all of them could serve the purpose... but I thought I'd share anyways.

[AnaFCPreto]

Looks like someone else already opened this issue here.
Apologies.