Skip Pull Request check in draft mode

[cegekaJG]

This PR adds a condition to "PullRequestHandler.yaml" that ensures pull requests in draft mode won't trigger the status check. This reduces unnecessary build workflows for feature branches. Additionally, the PR explicitly lists all types of the pull_request_target event. Listing the types isn't supposed to confirm each type as a valid reason to trigger the workflow, but rather to invite maintainers to judge which events can be ignored for this workflow. Resolves #1051