v3.0.0

• Move GPG_PRIVATE_KEY env var to gpg-private-key input
• Move PASSPHRASE env var to passphrase input
• Rename git_user_signingkey input to git-user-signingkey
• Rename git_commit_gpgsign input to git-commit-gpgsign
• Rename git_tag_gpgsign input to git-tag-gpgsign
• Rename git_push_gpgsign input to git-push-gpgsign
• Rename git_committer_name input to git-committer-name
• Rename git_committer_email input to git-committer-email
• Update deps