trigger CI when someone opens a PR

[jdrouet]

[nisargparikh69]

@jdrouet I can add this line in workflow files for cli, core, wasm .

on:
  pull_request:
      types: [ opened, synchronize, reopened ]

Plz let me know should i go ahead or you have other suggestions. Type:

1. opened is when PR created
2. synchronize is when commit is pushed to PR
3. reopened is when closed pull request is reopened