docs: fix tool name on readme page, copied from another orb (#8)

Co-authored-by: Justin Burr <juburr@users.noreply.github.com>

README.md

@@ -12,6 +12,6 @@ This is an unofficial Apko orb used for installing Apko in your CircleCI pipelin
 ### **Secure By Design**
 - **Least Privilege**: Installs to a user-owned directory by default, with no `sudo` usage anywhere in this orb.
 - **Integrity**: Checksum validation of all downloaded binaries using SHA-512.
-- **Provenance**: Installs directly from Cosign's official [releases page](https://github.com/sigstore/cosign/releases/) on GitHub. No third-party websites, domains, or proxies are used.
+- **Provenance**: Installs directly from Apko's official [releases page](https://github.com/chainguard-dev/apko/releases/) on GitHub. No third-party websites, domains, or proxies are used.
 - **Confidentiality**: All secrets and environment variables are handled in accordance with CircleCI's [security recommendations](https://circleci.com/docs/security-recommendations/) and [best practices](https://circleci.com/docs/orbs-best-practices/).
 - **Privacy**: No usage data of any kind is collected or shipped back to the orb developer.