-----> Building on the Heroku-20 stack
-----> Using buildpack: heroku/nodejs
-----> Node.js app detected
-----> Build failed
! Multiple lockfiles found
Multiple package managers (npm,Yarn) have created lockfiles for this application,
but only one can be used to install dependencies. Installing dependencies using the wrong package manager can result in missing
packages or subtle bugs in production.
Only one of the following package manager lockfiles are supported at a time:
- package-lock.json
- yarn.lock
- pnpm-lock.yaml
Please delete the lockfile(s) that should not be in use.
https://help.heroku.com/0KU2EM53
! Push rejected, failed to compile Node.js app.
! Push failed
Heroku fails because of this.