(actions): fix some dependabot actions issues

[everettraven]

Description of the change:

• Don't run the gpg and quay login steps for the jobs in https://github.com/operator-framework/operator-sdk/blob/master/.github/workflows/deploy.yml when Dependabot has created the PR. This makes it so CI can run properly on Dependabot PRs without Dependabot having access to secret values.

Motivation for the change:

• Make it possible for Dependabot PRs to pass CI so we can truly start taking advantage of the benefits of Dependabot

Checklist

If the pull request includes user-facing changes, extra documentation is required:

• Add a new changelog fragment in changelog/fragments (see changelog/fragments/00-template.yaml)
• Add or update relevant sections of the docs website in website/content/en/docs

[oceanc80]

/lgtm